Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| purification and characterization of helicobacter mustelae urease. | helicobacter mustelae is a urease-rich bacterium associated with gastritis in ferrets. the ureases of h. mustelae and helicobacter pylori, a bacterium implicated in human gastritis, share many characteristics. helicobacter sp. ureases appear to be unique among bacterial enzymes in exhibiting submillimolar km values and in being composed of two subunits. | 1991 | 1879950 |
| evaluation of campylobacter jejuni colonization of the domestic ferret intestine as a model of proliferative colitis. | forty 3- to 17-week old domestic ferrets, including 2 gnotobiotes, were inoculated orally and/or rectally with 10(6) to 10(9) colony-forming units of 1 or more of 4 strains of campylobacter jejuni, 3 of mink and 1 of human origin. feeding or gavage of any of the 4 strains, in milk or broth, with or without preinoculation sodium bicarbonate treatment to neutralize stomach acid, induced colonization in 38/40 ferrets; diarrhea lasted 2 to 4 days in conventional kits, 6 days in gnotobiotes. bacterem ... | 1991 | 1883085 |
| the effect of acidosis on the interval-force relation and mechanical restitution in ferret papillary muscle. | 1. the effect of a respiratory acidosis on the interval-force relation and on mechanical restitution was investigated in ferret papillary muscles. 2. acidosis (ph 6.85) decreased developed force over a range of stimulation frequencies (1.0.06 hz); the percentage decrease was greatest at the lowest stimulation frequencies. qualitatively similar effects of acidosis on developed force were observed in the presence of the sarcoplasmic reticulum (sr) inhibitor ryanodine. 3. mechanical restitution cur ... | 1991 | 1886064 |
| mn and cd transport by the na-ca exchanger of ferret red blood cells. | ca influx via the na-ca exchanger into ferret red blood cells is easily measured from a na-free solution; the intracellular na concentration is normally approximately 150 mm in ferret red blood cells. we have found that mn and cd competitively inhibit ca influx. mn influx and cd influx were a saturable function of the divalent cation concentration, consistent with a carrier mechanism. indeed, the km (approximately 10 microm) and the vmax (usually 1-3 mmol.l packed cells-1.h-1) were similar for c ... | 1991 | 1887874 |
| atropine-resistant submandibular responses to stimulation of the parasympathetic innervation in the anaesthetized ferret. | 1. submandibular salivary and vascular responses to stimulation of the peripheral end of the chorda-lingual nerve at 20 hz continuously for 60 min were investigated in anaesthetized ferrets, in which the sympathetic innervation to the gland was cut, in the presence and absence of atropine (2.0 mg kg-1). 2. both the increase in submandibular salivary flow and protein output, which occurred in response to nerve stimulation, were substantially reduced following the administration of atropine, the l ... | 1991 | 1890638 |
| the effects of metabolism on na(+)-k(+)-cl- co-transport in ferret red cells. | 1. the effects of altering metabolism on na(+)-k(+)-cl- co-transport were studied in ferret red cells. na(+)-k(+)-cl- co-transport was measured as the bumetanide-sensitive uptake of 86rb. 2. glucose, but not inosine or adenosine, sustained metabolism and maintained cell atp content ([atp]i) at the physiological level. [atp]i could be reduced by prolonged incubation of cells in a substrate-free medium or more quickly by incubating cells with 2-deoxyglucose or with a mixture of iodoacetamide and g ... | 1991 | 1890646 |
| characterization of eugonic fermenters group ef-4 by polyacrylamide gel electrophoresis and protein immunoblot analysis. | whole-cell lysates and proteinase k-extracted lipopolysaccharide (lps) of 19 strains of the group eugonic fermenter-4 (ef-4) were analyzed by electrophoresis and protein immunoblotting. these strains were isolated from dog- and cat-bite abscesses in human beings, ferret and human gastric lesions, and cat-lung infections. these strains represent 2 biovar groupings; ef-4a biovars ferment glucose and possess arginine dihydrolase activity, whereas ef-4b biovars do not. electrophoresis of whole-cell ... | 1991 | 1892260 |
| ferret tracheal epithelial cells grown in vitro are resistant to lethal injury by activated neutrophils. | airway inflammation is often accompanied by accumulation of polymorphonuclear leukocytes (pmn) as well as epithelial sloughing. to determine whether pmn contribute to epithelial damage in inflammatory states, we examined the interaction of pmn and tracheal epithelial cells in culture. ferret tracheal epithelial (fte) cells were grown in primary culture on collagen-coated multiwell dishes. confluent monolayers were loaded with [51cr]o4 and exposed to resting and activated neutrophils. there was n ... | 1991 | 1892642 |
| enzymatic conversion of beta-carotene into beta-apo-carotenals and retinoids by human, monkey, ferret, and rat tissues. | whether the conversion of beta-carotene into retinoids involves an enzymatic excentric cleavage mechanism was examined in vitro with homogenates prepared from human, monkey, ferret, and rat tissue. using high-performance liquid chromatography, significant amounts of beta-apo-12'-, -10'-, and -8'-carotenals, retinal, and retinoic acid were found after incubation of intestinal homogenates of the four different species with beta-carotene in the presence of nad+ and dithiothreitol. no beta-apo-carot ... | 1991 | 1899329 |
| amiloride delays the ischemia-induced rise in cytosolic free calcium. | an increase in cytosolic free calcium (cai) has been shown to occur early during ischemia in perfused rat, ferret, and rabbit hearts. it has been proposed that this increase in cai may occur as a result of exchange of nai for cao, which occurs as a result of an increase in nai arising from exchange of nao for h+i. the latter exchange is stimulated by the intracellular acidification that occurs during ischemia. to test this hypothesis, we examined cai, nai, atp, and phi during ischemia in rats in ... | 1991 | 1902148 |
| analysis of 23na nmr spectra from isolated perfused hearts. | the 23na nmr spectra obtained from isolated hearts perfused with buffer containing the paramagnetic shift reagent dysprosium triethylenetetraminehexaacetic acid, dy(ttha)3-, are complex and contain a number of overlapping peaks of different intensities. spectra from rat, rabbit, guinea pig, and ferret hearts obtained during periods of control perfusion are similar and undergo similar changes when the hearts are subjected to periods of ischemia and reflow. the contributions from the intracellular ... | 1991 | 1905777 |
| atp-dependent k+ channels modulate vasoconstrictor responses to severe hypoxia in isolated ferret lungs. | in normo- and hypoglycemic ferret lungs, the pulmonary vascular response to severe hypoxia (pio2 less than or equal to 10 mmhg) is characterized by an initial intense vasoconstriction followed by marked vasodilation, whereas in hyperglycemic lungs, vasodilation is minimal, causing vasoconstriction to be sustained. in contrast, the response to moderate hypoxia is characterized by a slowly developing sustained vasoconstriction which is unaffected by glucose concentration. to determine the role of ... | 1991 | 1907614 |
| characterization of beta-apo-13-carotenone and beta-apo-14'-carotenal as enzymatic products of the excentric cleavage of beta-carotene. | two new products from the incubation of beta-carotene with intestinal mucosa homogenates of human, monkey, ferret, and rat were isolated using high-performance liquid chromatography (hplc). identification by comparing retention times in hplc, by monitoring ultraviolet/visible spectra, by reduction to corresponding alcohol, by oxime formation, and by mass spectrometry demonstrated that they are beta-apo-13-carotenone and beta-apo-14'-carotenal. these compounds were not found in incubations done w ... | 1991 | 1911774 |
| pituitary adenylate cyclase-activating peptide (pacap), a new vasoactive intestinal peptide (vip)-like peptide in the respiratory tract. | pituitary adenylate cyclase-activating peptide (pacap) is a vasoactive intestinal peptide (vip)-like peptide recently isolated from ovine hypothalami. nerve fibers displaying pacap immunoreactivity were found in the respiratory tract of rats, guinea pigs, ferrets, pigs, sheep and squirrel monkeys. a moderate supply of pacap-immunoreactive fibers was seen in the nasal mucosa of guinea pigs. few to moderate numbers of pacap-containing fibers occurred in the tracheo-bronchial wall of rats, guinea p ... | 1991 | 1913779 |
| pancreatic adenocarcinoma with osseous metaplasia in a ferret. | a poorly differentiated pancreatic adenocarcinoma with regional lymphatic, hepatic, enteric and pulmonary metastases was diagnosed in an adult european ferret (mustela putoris furo). the ferret showed clinical signs including a progressive, marked abdominal enlargement owing to ascites. microscopic findings included intralesional osseous metaplasia. exocrine pancreatic neoplasms in ferrets are rarely reported compared with neoplasms with endocrine differentiation. | 1991 | 1918450 |
| morphology of pioneer and follower growth cones in the developing cerebral cortex. | in the developing nervous systems of both invertebrates and vertebrates, neurons must develop precise sets of axonal connections. one strategy used by both orders of animals is to generate a special class of neurons whose axons "pioneer" the first pathways between these cells and their targets. in the developing mammalian telencephalon, the subplate neurons (which are among the first neurons to be generated in development) extend axons to long-distance subcortical targets before the neurons of t ... | 1991 | 1919567 |
| experimental infection of domestic ferrets (mustela putorius furo) and siberian polecats (mustela eversmanni) with yersinia pestis. | eight domestic ferrets (mustela putorius furo) and two siberian polecats (m. eversmanni) were inoculated subcutaneously with 12 to 1.2 x 10(7) yersinia pestis originally isolated during an epizootic of plague in white-tailed prairie dogs (cynomys leucurus) near meeteetse, park county, wyoming (usa) in 1985. none of the ferrets or polecats developed clinical signs of disease which suggested that black-footed ferrets (m. nigripes), a congener, also would be resistant to plague. all animals receivi ... | 1991 | 1920664 |
| characterization of strains of helicobacter pylori: one-dimensional sds-page as a molecular epidemiologic tool. | one-dimensional linear sodium dodecyl sulfate-polyacrylamide gel electrophoresis of total proteins, coupled with a computerized numerical analysis, was used to distinguish among strains of helicobacter pylori. one hundred seventy-five clinical strains and five reference strains of h. pylori from humans, four isolates of helicobacter mustelae from ferrets, and three isolates of h. pylori-like organisms (hplos) from miniature swine were examined. intraspecies and interspecies comparisons were made ... | 1991 | 1925314 |
| effect of in vivo inhibition of neutrophil adherence on skeletal muscle function during ischemia in ferrets. | neutrophils are reported to play an important role in the genesis of tissue damage during reperfusion after periods of ischemia in a variety of organs and may also be involved in loss of tissue function during ischemia. to test this hypothesis, the monoclonal antibody, moab 60.3, which prevents the adhesion of ferret neutrophils to cultured human endothelial cells at a concentration of 30 micrograms/ml, was tested in a model of peripheral vascular disease to determine whether it would preserve s ... | 1991 | 1928400 |
| emd 53998 sensitizes the contractile proteins to calcium in intact ferret ventricular muscle. | emd 53998 (a thiadiazinone) is an inotropic drug that produces a pronounced increase in the ca2+ sensitivity of the contractile proteins in skinned cardiac fibers. the present study was undertaken to determine whether this effect on ca2+ sensitivity could explain the increase in tension observed in intact ventricular muscle. the experiments were performed on isolated ferret papillary muscles that had been microinjected with aequorin to measure the intracellular ca2+ concentration. force and intr ... | 1991 | 1934345 |
| contractile deactivation and uncoupling of crossbridges. effects of 2,3-butanedione monoxime on mammalian myocardium. | we investigated the effects of 1 and 3 mm 2,3-butanedione monoxime (bdm, diacetyl monoxime) on excitation and contraction of cardiac muscle in several types of preparations at various levels of organization. we selected a concentration of bdm that was not expected to affect sarcolemmal calcium flux and action potential duration in cardiac tissue. two indicators were used to record intracellular calcium. aequorin, a bioluminescent calcium indicator, was used in studies with ferret papillary muscl ... | 1991 | 1934358 |
| virulence of rimantadine-resistant human influenza a (h3n2) viruses in ferrets. | the influence of rimantadine-resistance mutations on the virulence of human h3n2 viruses in ferrets was examined. the similarities in virulence of the drug-resistant mutants with single amino acid substitutions at three different locations, 27, 30, and 31, within the m2 sequence and their corresponding sensitive wild-type isolates contrasted with differences in virulence between the three pairs of viruses. these data provide further evidence that rimantadine-resistant viruses that emerge during ... | 1991 | 1940477 |
| pathophysiology and pathogenesis of contractile failure in stunned myocardium. | to investigate excitation-contraction coupling in stunned myocardium, intracellular free calcium concentration [( ca2+]i) was measured before and after ischemia in perfused hearts using gated 19f nmr and the ca2+ indicator 5f-bapta. maximal ca(2+)-activated force was also measured in parallel experiments. stunned myocardium was created by reperfusion after 15 min global ischemia at 37 degrees c in isolated ferret hearts. in stunned myocardium, peak [ca2+]i was paradoxically higher than that in c ... | 1991 | 1942493 |
| dominant-negative mutants as antiviral agents: simultaneous infection with the cold-adapted live-virus vaccine for influenza a protects ferrets from disease produced by wild-type influenza a. | the attenuated cold-adapted strain of influenza a virus that is a candidate live-virus vaccine suppressed clinical disease in ferrets when given simultaneously with a virulent epidemic strain of influenza a virus. the cold-adapted virus effectively prevented disease, even when the epidemic strain was of a different subtype than the attenuated virus. in this case, ferrets given a mixed inoculum produced antibody to both subtypes in the absence of clinical disease, indicating that both viruses are ... | 1991 | 1955719 |
| delayed neurotoxic effects of bis (1-methylethyl) phosphorofluoridate (dfp) in the european ferret: a possible mammalian model for organophosphorus-induced delayed neurotoxicity. | this study examined the effects of the organophosphorus delayed neurotoxicant bis (1-methylethyl) phosphorofluoridate (dfp) on the central nervous system of the european ferret. animals received subcutaneous injections of either 2 or 4 mg dfp/kg b.w. the extent of neuropathology was determined by the fink-heimer method, the activities of neuropathy target esterase (nte) and cholinesterase (che) by enzyme assay methods, and the severity of clinical signs by a graded scale. in ferrets injected wit ... | 1991 | 1956582 |
| effects of aerosolized dexamethasone on acute subglottic injury. | aerosolized dexamethasone was used in a two-phase study to determine the possible effects on acute subglottic injury in the ferret animal model. in phase 1, equivalent subglottic injuries were made in 10 animals by using the brush technique, and the animals were divided into two groups. the treatment group received aerosolized dexamethasone at 2, 4, and 6 hours postinjury. all animals were examined 2, 4, 6, and 24 hours after the injury. the clinical condition of each animal was evaluated and th ... | 1992 | 1728893 |
| beta-carotene uptake and tissue distribution in ferrets (mustela putorius furo). | ferrets accumulate beta-carotene in liver and adipose tissue after chronic feeding. this study was designed to further evaluate the time course of uptake and depletion of beta-carotene in ferret serum and tissues. male ferrets (n = 15; 1000-1200 g) were given a single dose of beta-carotene (10 mg/kg body wt) with a meal. animals were killed at various time points over an 11-d period. blood and tissue samples were extracted and analyzed for beta-carotene by hplc. peak serum beta-carotene levels ( ... | 1992 | 1729459 |
| host species-specific antigenic variation of a mannosylated surface glycoprotein of pneumocystis carinii. | all pneumocystis carinii, irrespective of their host of origin, express an abundant mannosylated surface glycoprotein. while this molecule is commonly referred to as gp120, some variation in the size of this molecule has been noted. monoclonal antibodies produced to this molecule from ferret, mouse, rat, and human p. carinii made it possible to distinguish the glycoprotein from p. carinii of each host by immunoblot and indirect immunofluorescence assays. the glycoprotein varied in size (approxim ... | 1992 | 1730900 |
| immunohistochemical evidence for transient expression of fibronectin in the developing dorsal lateral geniculate nucleus of the ferret. | in recent years, the important role of the extracellular matrix in neural development has been increasingly recognized. in order to begin to examine what role might be played by the extracellular matrix in the developing dorsal lateral geniculate nucleus (dlgn), the present study used immunocytochemistry to assess the distribution of a recognized extracellular matrix molecule, fibronectin (fn), during postnatal development of the ferret dlgn. prior to the segregation of cell layers, no clear pat ... | 1992 | 1740545 |
| haemagglutination profiles of helicobacter species that cause gastritis in man and animals. | thirty-five helicobacter pylori isolates, 21 h. mustelae isolates and four strains of h. felis were compared for their ability to agglutinate red blood cells (rbcs). isolates were examined in a slide haemagglutination assay with rbcs from 11 animal species, including rodents, carnivores and primates, as well as man. rbcs were agglutinated by 65-90% of h. mustelae isolates and 16-57% of h. pylori isolates. treatment of h. mustelae with pronase and heat inhibited haemagglutination (ha) whereas hea ... | 1992 | 1279175 |
| origin and fate of fetuin-containing neurons in the developing neocortex of the fetal sheep. | the development of the neocortex has previously been extensively studied in carnivores (cat and ferret), rodents (rat and mouse) and primates (monkey and human). in these species, it has been shown that the initial population of cells migrating from the ventricular zone forms the primordial plexiform layer. this is subsequently split into marginal zone and subplate zone by the insertion of later-migrating cells into the primordial plexiform layer, to form the cortical plate proper. many of the c ... | 1992 | 1280010 |
| nitric oxide synthase in ferret brain: localization and characterization. | 1. in the present study, we have investigated the distribution of nitric oxide synthase in the ferret brain. nitric oxide synthase was determined biochemically and immunochemically. 2. in the rat brain, the highest nitric oxide synthase activity has been detected in the cerebellum. however, in the ferret brain, the highest activity was found in the striatum and the lowest in the cerebellum and cerebral cortex. the enzymatic activity was localized predominantly in the cytosolic fractions, it was ... | 1992 | 1282076 |
| cyclic gmp inhibits the inotropic response to alpha 1-adrenoceptors in the papillary muscle of the ferret. | the physiological role of cyclic gmp in the heart remains controversial. in the present study we investigated the interaction between a number of agents known to increase the level of cyclic gmp in the myocardium and alpha 1-adrenergic stimulation in isolated preparations of cardiac papillary muscle in the ferret. inotropic responses to the cumulative addition of phenylephrine were measured in papillary muscles of the ferret in the absence and presence of 1 microm sodium nitroprusside, 1 microm ... | 1992 | 1282377 |
| ventricular function and calcium handling during ischemia. | ischemia-induced ventricular dysfunction has been shown to be associated with increased diastolic and systolic intracellular concentrations of free, ionized calcium ([ca2+]i). the present study was designed to determine the effects of the calcium antagonist nisoldipine on the relationship between [ca2+]i and left ventricular contraction and relaxation during ischemia and reperfusion on a beat-to-beat basis. nine isovolumic coronary-perfused ferret hearts were made globally ischemic for 3 min and ... | 1992 | 1282612 |
| photoperiod modulates pubertal shifts in behavioral responsiveness to testosterone. | this study examined the effect of photoperiod on pubertal maturation of steroid-dependent reproductive behaviors in male european ferrets (mustela putorius furo). in the first experiment, levels of neck gripping, mounting, and pelvic thrusting in gonadally intact prepubertal (pre) ferrets were compared with those of adults that had undergone puberty either while housed in short days (8 hr light/16 hr darkness per day; sd), or after transfer from sd to long days (18 hr light/6 hr darkness per day ... | 1992 | 1286204 |
| multiple motor pathways to single smooth muscle cells in the ferret trachea. | 1. we investigated the distribution and characteristics of motor pathways to individual smooth muscle cells activated by electrical stimulation of either, single nerves which enter the tracheal plexus (inlet nerves), or a longitudinal nerve trunk (lnt) located near the entrance of an inlet nerve into the plexus. excitatory junction potentials (ejps) were recorded using intracellular microelectrodes as an index of smooth muscle cell activation. in all experiments ejps were completely blocked by t ... | 1992 | 1293288 |
| two components of the pineal organ in the mink (mustela vison): their structural similarity to submammalian pineal complexes and calcification. | the pineal complex in the mink (mustela vison) consists of a larger ventral and a smaller dorsal pineal. both organs contain pinealocytes, neurons, glial cells, nerve fibers and synapses in an organization characteristic of nervous tissue. the cellular elements are arranged circularly around strait lumina. these lumina correspond to the photoreceptor spaces of submammalian pineals. a 9 + 0-type cilium marks the receptory pole of the pinealocytes which may form an inner-segment-like dendrite term ... | 1992 | 1295547 |
| [the fever reaction of the polecat mustela putorius x mustela putorius furo to a bacterial pyrogen: the hypo- and hyperthermic phases]. | it has been demonstrated that the ferret (mustela putorius x mustela putorius furo) responds to intramuscular injection of salmonella typhi lipopolysaccharide (30 ng/kg-100 micrograms/kg) by biphasic change in the body temperature (tb): the initial decrease in the latter is followed by hyperthermia. maximum rise in tb (1.6 +/- 0.1 degrees c) was observed after the injection of lipopolysaccharide in the highest dose. rabbit leucocytic pyrogen/interleukin-1 (1 ml from 3.5 x 10(7) peritoneal phagoc ... | 1992 | 1302417 |
| development of high-affinity 5-ht3 receptor antagonists. 1. initial structure-activity relationship of novel benzamides. | this report describes the development of novel benzamides which are orally active, highly potent, specific antagonists of 5-ht3 receptors. described in this first report are the structure-activity relationships that led to novel structures with improved potency and selectivity. from this series of compounds, (s)-28 was identified and selected for further evaluation as a 5-ht3 receptor antagonist. compared with 5-ht3 antagonists such as gr 38032f, brl 43694, and metoclopramide, (s)-28 was most ac ... | 1992 | 1312602 |
| characterization of a new avian-like influenza a virus from horses in china. | in march 1989 a severe outbreak of respiratory disease occurred in horses in the jilin and heilongjiang provinces of northeast china that caused up to 20% mortality in some herds. an influenza virus of the h3n8 subtype was isolated from the infected animals and was antigenically and molecularly distinguishable from the equine 2 (h3n8) viruses currently circulating in the world. the reference strain a/equine/jilin/1/89 (h3n8) was most closely related to avian h3n8 influenza viruses. sequence comp ... | 1992 | 1314452 |
| cellular mechanisms that control pulmonary vascular tone during hypoxia and normoxia. possible role of ca2+atpases. | we investigated cellular mechanisms that may be involved in controlling cytosol calcium and pulmonary artery pressure during hypoxia and normoxia in isolated blood-perfused ferret lungs. alveolar hypoxia in ferret lungs causes an active increase in pulmonary vascular resistance. hypoxic pulmonary vasoconstriction directly correlates with extracellular calcium ([ca2+]o), and the absence of [ca2+]o in the perfusate markedly attenuates the hypoxemia-induced pulmonary vasoconstriction. alveolar hypo ... | 1992 | 1317692 |
| are all 5-ht3 receptor antagonists the same? | a number of 5-ht3 receptor antagonists are currently in clinical development as antiemetics. in this paper we focus on two of these antagonists, granisetron and ondansetron, and compare their antimetic activity against cisplatin (10 mg/kg i.v.)- or whole body x-irradiation (200 rads)-induced emesis in the conscious ferret. the results presented here have been discussed in the light of the recently published literature. our data suggest that in comparison to ondansetron, granisetron is a more pot ... | 1992 | 1320915 |
| contractile agonists activate voltage-dependent calcium channels in airway smooth muscle cells. | to determine whether agents that cause contraction of airway smooth muscle affect sarcolemmal calcium channel activity, unitary calcium channel currents (using ba2+ as the charge carrier) were recorded in on-cell configuration from acutely dissociated (dog, pig, and ferret) and cultured (human) airway smooth muscle cells. addition of the contractile agonists methacholine or bradykinin increased the open-state probability of the large-conductance calcium channel 37.2- and 45-fold, respectively. t ... | 1992 | 1322035 |
| endothelin reverses the effects of acidosis on the intracellular ca2+ transient and contractility in ferret myocardium. | endothelin may play an important role in modulating myocardial contractility under certain pathophysiological conditions. to determine whether endothelin beneficially modulates myocardial contractility in the common clinical condition of acidosis, we compared the effects of endothelin-1 on intracellular ca2+ transients and isometric contractions under normal (extracellular ph [ph(o)] 7.4) and acidotic (ph(o) 6.4) conditions in ferret papillary muscles (n = 33) loaded with the ca(2+)-regulated bi ... | 1992 | 1323435 |
| morphine 6-glucuronide: a metabolite of morphine with greater emetic potency than morphine in the ferret. | 1. the emetic potencies of morphine and its metabolite morphine 6-glucuronide have been determined in the ferret by constructing dose-response curves for mean total retches and vomits for subcutaneous doses of 0.05 mg kg-1 to 5 mg kg-1. morphine 6-glucuronide induced retching and vomiting at lower doses than morphine and at a maximal dose induced more retching and vomiting than morphine. 2. the emesis induced by both morphine and morphine 6-glucuronide was abolished by the preadministration of n ... | 1992 | 1324067 |
| differential inotropic effects of flosequinan in ventricular muscle from normal ferrets versus patients with end-stage heart failure. | 1. in right ventricular papillary muscles from control ferrets, flosequinan (10(-7)-10(-4) m) produced a concentration-dependent positive inotropic effect (10(-5) m = 153 +/- 24, 10(-4) m = 198 +/- 44% increase in isometric tension; control tension = 100%; n = 11) associated with a corresponding increase in amplitude of the intracellular ca2+ ([ca2+]i) transient recorded with aequorin (10(-5) m = 133 +/- 11, 10(-4) m = 187 +/- 36% increase in [ca2+]i transient; n = 11). 2. the positive inotropic ... | 1992 | 1324072 |
| the neuropharmacology of loperamide-induced emesis in the ferret: the role of the area postrema, vagus, opiate and 5-ht3 receptors. | loperamide, an opiate receptor agonist, commonly used in the treatment of diarrhoea, reliably induced emesis in the ferret, when given subcutaneously. the response latency was short (less than 10 min) and the emesis lasted for approx 70 min. the dose-response curve for the emetic response was "bell-shaped" and all animals responded at 0.5 mg/kg but none at 5 mg/kg (s.c.). the response was unaffected by dopamine d2 receptor antagonism (domperidone 1.0 mg/kg, s.c.) or 5-ht3 receptor antagonism (gr ... | 1992 | 1326727 |
| expression of na(+)-k(+)-atpase alpha 1- and alpha 3-isoforms in adult and neonatal ferret hearts. | we have demonstrated previously that in adult ferret heart two alpha-subunit isoforms of the na(+)-k(+)-atpase, alpha(+) and alpha, are expressed. the alpha(+)-isoform may comprise either alpha 2-, or alpha 3-, or both isoforms. the present studies further characterize the alpha(+)-isoform. the alpha(+)-isoform of ferret heart did not react with an alpha 2-specific monoclonal antibody, but rather with two different alpha 3-specific polyclonal antibodies. electrophoretic mobility of the alpha(+)- ... | 1992 | 1332511 |
| relationship between vomiting and taste aversion learning in the ferret: studies with ionizing radiation, lithium chloride, and amphetamine. | the relationship between emesis and taste aversion learning was studied in ferrets (mustela putorius furo) following exposure to ionizing radiation (50-200 cgy) or injection of lithium chloride (1.5-3.0 meq/kg, ip). when 10% sucrose or 0.1% saccharin was used as the conditioned stimulus, neither unconditioned stimulus produced a taste aversion, even when vomiting was produced by the stimulus (experiments 1 and 2). when a canned cat food was used as the conditioned stimulus, lithium chloride, but ... | 1992 | 1333765 |
| antibodies, implantation and embryo survival. | the diverse strategies adopted among species for the maintenance of luteal function converge to meet the indispensable requirement for this hormone particularly at the time of onset of implantation. what has emerged from immunization studies is the difference that exists between various species in the effects of progesterone depletion. the findings affirm the uterus as a primary site of progesterone action in the preimplantation period of gestation in the mouse, whereas in the hamster the positi ... | 1992 | 1338606 |
| retinogeniculate epsps recorded intracellularly in the ferret lateral geniculate nucleus in vitro: role of nmda receptors. | we used an in vitro preparation of the ferret lateral geniculate nucleus (lgn) to examine the role of the nmda class of excitatory amino acid (eaa) receptors in retinogeniculate transmission. intracellular recordings revealed that blockade of nmda receptors both shortened the time course and reduced the amplitude of fast and slow components of excitatory postsynaptic potentials (epsps) evoked by optic tract stimulation. the amplitude and width of the epsps mediated by nmda receptors increased as ... | 1992 | 1350209 |
| immunocytochemistry and calcium cytochemistry of the mammalian pineal organ: a comparison with retina and submammalian pineal organs. | morphologically the mammalian pineal organ is a part of the diencephalon. it represents a neural tissue histologically ("pineal nervous tissue") and is dissimilar to endocrine glands. submammalian pinealocytes resemble the photoreceptor cells of the retina, and some of their cytologic characteristics are preserved in the mammalian pinealocytes together with compounds demonstrable by cyto- and immunocytochemistry and participating in photochemical transduction. in our opinion, the main trend of t ... | 1992 | 1351408 |
| potential for hepatic and renal dysfunction during influenza b infection, convalescence, and after induction of secondary viremia. | whether infection with influenza b virus alters hepatic function was examined in the ferret. also, the possibility that viral-specific antibodies (ab) could be produced well before their detection in serum was explored. during the febrile period of influenza, reductions in the serum potassium, anion gap, ammonia, albumin and cpk and elevations of the bun, creatinine and the ggtp levels occurred. with convalescence, the electrolytes, bun and creatinine normalized, ffa, sgpt and cpk levels rose an ... | 1992 | 1352541 |
| evidence for an atypical, or beta 3-adrenoceptor in ferret tracheal epithelium. | 1. a preparation of the ferret trachea in vitro was used to examine the effects of three selective beta-adrenoceptor agonists on lysozyme secretion from submucosal gland serous cells and epithelial albumin transport into tracheal mucus following sustained, submaximal stimulation of mucus production with methacholine (20 microm). 2. prenalterol, salbutamol and brl 37344 all enhanced methacholine-induced albumin output. brl 37344 was 10,000 times more potent than salbutamol, and salbutamol was sli ... | 1992 | 1354537 |
| surgical and pharmacological dissociation of cardiovascular and emetic responses to intragastric cuso4. | under control (intact and laparotomized) conditions, arterial pressure of urethan-anesthetized ferrets rose significantly in response to intragastric copper sulfate (cuso4; 10 ml of 5 mg/ml). cuso4 was emetic 75-90% of the time, and a cardiovascular response always immediately preceded and accompanied emetic responses. the cardiovascular response was significantly reduced or abolished by hexamethonium (0.35 mg/kg) pretreatment combined with atropine methyl bromide (1 mg/kg). addition of the alph ... | 1992 | 1354943 |
| ferret red cells: na/ca exchange and na-k-cl cotransport. | the primary pathway for k influx in ferret red cells is the na-k-cl cotransporter and the primary pathway for ca influx is the na/ca exchanger. this makes ferret red cells favorable models for the study of these two transport systems. the evidence that na/ca exchange is of primary importance for steady state cell volume regulation and the na-k-cl cotransport has a minor role is presented. the approaches to, and results of, the determination of the stoichiometry, of the mechanism, and of the regu ... | 1992 | 1355025 |
| hematological and plasma chemical characteristics in beech marten (martes foina). | 1. the normal values of hematological and clinical-chemical variables in plasma of 21 males and 27 females of beech marten (martes foina) have been illustrated and compared to corresponding normal values in mink (mustela vison) and ferret (mustela putorius). 2. the number of erythrocytes, the hematocrit value, and the hemoglobin concentration were higher in male than in female beech marten. 3. divergences according to age in the investigated variables have been found. 4. the erythrocytes in beec ... | 1992 | 1355036 |
| [arrhythmogenic effects of sultopride chlorhydrate: clinical and cellular electrophysiological correlation]. | this study was designed following the first documented case of torsades de pointes induced by sultopride hydrochloride, a substituted benzamide neuroleptic drug. the patient, a 48 year-old woman with no known cardiovascular disease, had been treated for several years with this drug. she was admitted for severe bronchospasm requiring artificial ventilation. twenty-one hours after her admission, she developed several episodes of torsades de pointes, which were successfully treated with magnesium s ... | 1992 | 1363741 |
| helicobacter mustelae isolation from feces of ferrets: evidence to support fecal-oral transmission of a gastric helicobacter. | helicobacter mustelae has been isolated from stomachs of ferrets with chronic gastritis and ulcers. when h. mustelae is inoculated orally into h. mustelae-negative ferrets, the animals become colonized and develop gastritis, a significant immune response, and a transient hypochlorhydria. all of these features mimic helicobacter pylori-induced gastric disease in humans. because the epidemiology of h. pylori infection is poorly understood and its route of transmission is unknown, the feces of wean ... | 1992 | 1370432 |
| neutrophil elastase stimulates tracheal submucosal gland secretion that is inhibited by ici 200,355. | to investigate whether human neutrophil elastase (hne) stimulates airway submucosal gland secretion, we studied the effect of purified hne on secretion of 35s-labeled macromolecules from isolated tracheal tissues from ferrets, dogs, and humans. hne stimulated secretion in a concentration-dependent fashion, the secretory response being most pronounced in ferret tissues with a maximal response of 1,498 +/- 384% above baseline at 10(-5) m. in dog tissues, maximal secretory responses (509 +/- 169%) ... | 1992 | 1370750 |
| viral infection increases contractile but not secretory responses to substance p in ferret trachea. | viral infection increases the airway smooth muscle response to substance p. this effect is due to decreased activity of neutral endopeptidase (ec 3.4.24.11), an enzyme that degrades substance p. inhibition of neutral endopeptidase activity also potentiates substance p-induced 35so4-labeled macromolecule secretion. therefore we examined the in vitro effects of substance p on 35so4-macromolecule secretion from the tracheae of influenza-infected ferrets. despite a virus-induced loss of neutral endo ... | 1992 | 1373130 |
| distributions of interstitial cells of cajal in stomach and colon of cat, dog, ferret, opossum, rat, guinea pig and rabbit. | electrical slow waves vary in prominence from one location to another in stomach and colon. if interstitial cells of cajal are involved in generation of the slow waves, they might be more abundant in regions where slow waves are prominent than in regions where slow waves are small or absent. we calculated the density of distribution of interstitial cells of cajal in colon and stomach of cat, dog, ferret, guinea pig, opossum, rabbit, and rat, using the zinc iodide-osmic acid reaction for light mi ... | 1992 | 1375611 |
| cytoplasmic estrogen receptors in rat brain: immunocytochemical evidence using three antibodies with distinct epitopes. | the existence of cytoplasmic estrogen receptors (ers) has been reported in the guinea pig brain using immunocytochemical techniques. while cytoplasmic ers have been reported recently in other species, such as opossum, musk shrew, and ferrets, an exclusively cell nuclear pattern of er immunoreactivity has been reported in the rat brain. because all studies that have reported the existence of cytoplasmic ers in the brain have used the h 222 monoclonal antibody, the possibility exists that this obs ... | 1992 | 1380440 |
| cytoarchitectonic heterogeneities in the thalamic reticular nucleus of cats and ferrets. | the thalamic reticular nucleus has been classically defined as a group of cells surrounding most of the rostral and lateral surfaces of the dorsal thalamus, lateral to the fibres of the external medullary lamina and medial to those of the internal capsule. with the use of nissl staining and antibodies to gamma-aminobutyric acid (gaba), somatostatin, and parvalbumin, this study describes the cytoarchitecture of the thalamic reticular nucleus of cats and ferrets. in cats, three subdivisions of the ... | 1992 | 1381730 |
| regulation of vascular smooth muscle tone by caldesmon. | caldesmon is an actin-binding protein present in smooth muscle cells that also inhibits actin-activated myosin atpase activity. to assess the possible role of caldesmon in the regulation of smooth contraction, we investigated the effects of synthetic peptides on force directly recorded from single hyperpermeable smooth muscle cells of ferret aorta and portal vein. gs17c, a peptide that contains the residues from gly651 to ser667 of the caldesmon sequence plus an added cysteine at the c terminus, ... | 1992 | 1386078 |
| external calcium sensitivity of low sodium contractures in the control and hypertrophied right ventricle of the ferret. | the existence of possible differences of calcium (ca2+) fluxes through the sarcolemmal sodium-calcium (na+/ca2+) exchanger during hypertrophy has been tested by comparing the characteristics of the contracture--as an indicator of the intracellular ca2+ concentration--induced by partial or total withdrawal of external sodium (na+), in the absence of external potassium, in the right ventricular trabeculae of adult ferret hearts. pressure-overload was induced by pulmonary artery clipping and led to ... | 1992 | 1386173 |
| choline acetyltransferase expression studied with an oligonucleotide probe. | 1. the localization of choline acetyltransferase messenger rna has been studied using a digoxigenin-tailed complementary oligodeoxynucleotide probe for in situ hybridization. 2. putative cholinergic cells of the rat and ferret spinal cord and the ferret retina were labeled. 3. this technique affords superior resolution compared to radioactively labeled probes, with apparently equal sensitivity. | 1992 | 1394369 |
| myocardial energetics during ventricular fibrillation investigated by magnetization transfer nuclear magnetic resonance spectroscopy. | ventricular fibrillation (vf) is known to produce alterations in myocardial energetics, but the mechanism of these changes remains unclear. to investigate energy metabolism during vf, phosphorus nuclear magnetic resonance spectroscopy and magnetization transfer were applied to isolated perfused ferret hearts. vf was induced either by perfusion with digitalis (strophanthidin, 30 microm) or by high-frequency electrical stimulation. we measured the flux in two critical reactions: from inorganic pho ... | 1992 | 1394873 |
| pulmonary venous pressure increases during alveolar hypoxia in isolated lungs of newborn pigs. | the purpose of this study was to determine whether pulmonary venous pressure increases during alveolar hypoxia in lungs of newborn pigs. we isolated and perfused with blood the lungs from seven newborn pigs, 6-7 days old. we maintained blood flow constant at 50 ml.min-1.kg-1 and continuously monitored pulmonary arterial and left atrial pressures. using the micropuncture technique, we measured pressures in 10 to 60-microns-diam venules during inflation with normoxic (21% o2-69-74% n2-5-10% co2) a ... | 1992 | 1399980 |
| position of growth cones within the retinal nerve fibre layer of fetal ferrets. | optic axons are added to the retinal nerve fibre layer of fish along its vitreal border in a chronotopic manner. likewise, the optic tract of all vertebrate species acquires axons preferentially along the superficial surface of the pathway. we have examined the developing retina of fetal ferrets (mustela putorius furo) aged between embryonic day 27 (e27) and e34 to see whether a similar segregation of growth cones is apparent within the mammalian retinal nerve fibre layer. the distributions of g ... | 1992 | 1401254 |
| cellular mechanisms of paired electrical stimulation in ferret ventricular myocardium: relationship between myocardial force and stimulus interval change. | the subcellular mechanisms of twitch-force potentiation with paired electrical stimulation was studied in ferret ventricular myocardium using the bioluminescent calcium indicator aequorin. it is demonstrated for the first time that interpolation of an extrasystole in a train of conditioned twitches results in a beat-to-beat change in [ca2+]i and force. steady-state twitch force and ca2+i were increased with paired stimulation. increased [ca2+]o in the setting of paired stimulation resulted in an ... | 1992 | 1401334 |
| expression and characterization of a cdna clone encoding an immunodominant surface glycoprotein of pneumocystis carinii. | most studies of antigens of pneumocystis carinii have focused on an abundant, immunogenic 95- to 140-kda surface glycoprotein referred to as gpa. expression cloning of gpa from p. carinii obtained from ferrets resulted in isolation of colinear fragments of gpa cdna encoding approximately 87 kda of the core protein. northern hybridization detected an abundant, single species of gpa-specific mrna of 3600 nucleotides. southern hybridization revealed gpa-specific bands only in p. carinii-infected lu ... | 1992 | 1402023 |
| ultrastructural quantitation of mitochondria and myofilaments in cardiac muscle from 10 different animal species including man. | the ultrastructural quantitative composition of normal myocardial cells has been studied in 10 different species: man, dog, pig, cat, rabbit, ferret, guinea-pig, rat, mouse, and bat. volume densities of mitochondria, myofibrils, and cytoplasm were determined using morphometry. it was found that the content of mitochondria differs in various species ranging between 22.0-37.0%. it is a very specific and constant value for any particular species, the smallest having the highest content. a close cor ... | 1992 | 1404407 |
| lhrh in the ferret: pubertal decrease in the number of immunopositive arcuate neurons. | this study correlated a region-specific change in the number of luteinizing hormone-releasing hormone-immunopositive (lhrh+) neurons with pubertal development in male ferrets. there were 50% fewer lhrh+ cell bodies in the arcuate nucleus of peri- and postpubertal ferrets than in prepubertal ferrets; this significant decrease represented a 15% reduction in the overall number of lhrh+ neurons. intracerebroventricular colchicine did not reveal additional numbers of lhrh+ neurons in the arcuate nucl ... | 1992 | 1409003 |
| membrane and synaptic properties of developing lateral geniculate nucleus neurons during retinogeniculate axon segregation. | during the first postnatal month in the ferret (mustela putorius furo), the projections from the retina to the lateral geniculate nucleus (lgn) become segregated into eye-specific layers and on and off sublayers, a process that is thought to depend in part on neuronal activity. remarkably, virtually nothing is known about the physiological features of lgn neurons during this period. we have recorded intracellularly from 46 a-layer neurons in slices of the ferret lgn between the ages of postnatal ... | 1992 | 1409711 |
| sexual dimorphism in the effects of mating on the in vitro release of lhrh from the ferret mediobasal hypothalamus. | a sexually dimorphic pattern in the secretion of luteinizing hormone (lh) has previously been shown to occur in response to mating in an induced ovulating species, the ferret, with mating augmenting the secretion of lh in females but not in males. the aim of this study was to determine whether this dimorphic pattern in the postcoital secretion of lh reflects a dimorphic effect of mating on the neural release of luteinizing hormone releasing hormone (lhrh). the effect of mating on the in vitro re ... | 1992 | 1409957 |
| discovery of a peptide-based renin inhibitor with oral bioavailability and efficacy. | peptidic renin inhibitors have been poorly absorbed across the intestine or rapidly eliminated by the liver and have been reported to have oral bioavailabilities of less than 2%. a peptide-based renin inhibitor, a-72517 (molecular mass of 706 daltons), was devised that has oral bioavailabilities of 8, 24, 32, and 53% in the monkey, rat, ferret, and dog, respectively. dose-related reductions in blood pressure, plasma renin activity, and plasma angiotensin ii in parallel with increased plasma drug ... | 1992 | 1411510 |
| hepatic mixed-function oxidases of ferret. | 1. ferret liver mixed-function oxidase enzymes have been quantified using a variety of substrates and the activities have been compared with those found in rat liver. 2. ferret liver total cytochrome p-450 is only 30% of that of rat liver and exhibits higher 7-ethoxyresorufin o-deethylase (erod) activity, and lower lauric acid hydroxylase activity than rat liver; other mixed-function oxidases are at similar levels of activity in both species. 3. induction with 3-methylcholanthrene (mc), similar ... | 1992 | 1413877 |
| the attenuation phenotype conferred by the m gene of the influenza a/ann arbor/6/60 cold-adapted virus (h2n2) on the a/korea/82 (h3n2) reassortant virus results from a gene constellation effect. | a single gene reassortant (sgr) virus that derived its m gene from the attenuated influenza a/ann arbor/6/60 cold-adapted (ca) donor virus and the remaining genes from the a/korea/82 (h3n2) wild type (wt) virus (designated a/korea/82 ca m-sgr) was previously shown to be attenuated in mice, hamsters, ferrets, and humans. the attenuation (att) phenotype of this sgr virus could result directly from an altered function of the mutant m gene product of the a/ann arbor/6/60 ca virus, which differs from ... | 1992 | 1413993 |
| ca(2+)-independent isoforms of protein kinase c differentially translocate in smooth muscle. | it is generally assumed that smooth muscle contraction is dependent on changes in intracellular ca2+ concentration ([ca2+]i); however, we have previously reported that alpha-agonist-induced contraction of aorta smooth muscle cells can occur in the absence of changes in [ca2+]i [collins, e. m., m. p. walsh, and k. g. morgan. am. j. physiol. 262 (heart circ. physiol. 31): h754-h762, 1992]. the mechanism of this [ca2+]i-independent contraction is controversial. we have now identified the ca(2+)-ind ... | 1992 | 1415520 |
| intestinal uptake and lymphatic absorption of beta-carotene in ferrets: a model for human beta-carotene metabolism. | to determine the appropriateness of the ferret as a model for human beta-carotene (beta-c) metabolism, we have perfused both 15,15'-beta-[14c]c and unlabeled beta-c through the upper 30-cm portion of the small intestine of ferrets in vivo. the effluents of a mesenteric lymph duct cannulation and a common bile duct cannulation, as well as portal vein blood periodically sampled via an indwelling catheter, were collected. ten percent (9.5 +/- 0.06%) of the total administered beta-c was taken up by ... | 1992 | 1415707 |
| the l type calcium current in single hypertrophied cardiomyocytes isolated from the right ventricle of ferret heart. | the aim was to study l type calcium current alterations in relation to the action potential lengthening induced by hypertrophy in isolated cardiomyocytes from the right ventricle of ferret. | 1992 | 1423430 |
| decreased myofilament responsiveness in myocardial stunning follows transient calcium overload during ischemia and reperfusion. | the purpose of this study was to test the hypothesis that abnormal intracellular calcium handling characterizes myocardial stunning. isolated, isovolumic, buffer-perfused ferret hearts were loaded with the bioluminescent calcium indicator aequorin for simultaneous measurement of individual calcium transients and left ventricular pressure. after 15 minutes of global ischemia and 20 minutes of reperfusion, left ventricular developed pressure was significantly reduced (75 +/- 7 versus 93 +/- 6 mm h ... | 1992 | 1423931 |
| 5-ht3 receptor antagonist effects of dat-582, (r) enantiomer of as-5370. | the serotonin 5-ht3 receptor antagonist effects of dat-582, the (r) enantiomer of as-5370 ((+/-)-n-[1-methyl-4-(3-methyl-benzyl)hexahydro-1h-1,4-diazepin-6- yl]-1h- indazole-3-carboxamide dihydrochloride), and its antipode were compared with those of as-5370 and existing 5-ht3 receptor antagonists. in anesthetized rats, dat-582 antagonized 2-methyl-5-ht-induced bradycardia with an ed50 value of 0.25 microgram/kg i.v., whereas the (s) enantiomer was without effect even at 1000 micrograms/kg i.v. ... | 1992 | 1425931 |
| lucifer yellow, retrograde tracers, and fractal analysis characterise adult ferret retinal ganglion cells. | the dendritic morphology of retinal ganglion cells in the ferret was studied by the intracellular injection of lucifer yellow in fixed tissue. ganglion cells were identified by the retrograde transport of red or green fluorescent microspheres that had been injected into different target nuclei, usually the lateral geniculate nucleus or superior colliculus. this approach allows the comparison of dendritic morphologies of ganglion cells in the same retina with different central projections and als ... | 1992 | 1430318 |
| effects of sex and androgen treatment on dendritic dimensions of neurons in the sexually dimorphic preoptic/anterior hypothalamic area of male and female ferrets. | a sexually dimorphic group of cells at the dorsal border of the preoptic/anterior hypothalamic area (poa/ah) of ferrets has been previously identified in nissl-stained tissue. in this study, golgi-stained tissue was examined in order 1) to determine whether sex differences exist in dendritic dimensions of neurons from this region, and 2) to assess the effects of adult androgen treatment on dendritic morphology in ferrets of both sexes. brains from adult ferrets given daily injections of testoste ... | 1992 | 1430324 |
| ultrastructural development of the medial superior olive (mso) in the ferret. | when ferrets are born, four weeks before the onset of hearing, few synapses are evident in the medial superior olive (mso). the synapses present are immature and almost exclusively found in the neuropil. the mso somata are virtually devoid of synaptic contacts but are contacted by fine glial processes that increasingly ensheathe the somata during the first postnatal week. by p12, somatic synaptogenesis in the mso is evident. initially the terminals contain vesicles of irregular shape, size, and ... | 1992 | 1430336 |
| biocompatibility of retrograde filling materials in the ferret canine. amalgam and irm. | periapical tissue response to retrograde fillings of amalgam and irm were compared in the mandibular canine of the adult male ferret. teeth were cleaned and shaped with a standard technique and obturated with gutta-percha. the root apex was then exposed and retrofillings were placed. the animals were grouped according to observation periods of 5, 10, and 15 weeks. at the proper time the animals were killed and the lower canine tooth along with the surrounding bone was removed. the tissue blocks ... | 1992 | 1437046 |
| effect of ovariectomy on blastocyst expansion and survival in ferrets (mustela putorius furo). | the initial objective was to investigate whether progesterone alone can support full blastocyst expansion in ferrets ovariectomized on day 5 post coitum (p.c.). by day 11 p.c. blastocysts from control animals had expanded to approximately 2000 microns in diameter, whereas by days 11 or 14 p.c. blastocysts from ovariectomized animals given progesterone had diameters of < 1000 microns. thus, ovarian factors in addition to progesterone are apparently required for normal blastocyst expansion in this ... | 1992 | 1438953 |
| force production in voltage-clamped human atrial muscle. | human atrial muscle preparations obtained during open heart surgery were mounted in a sucrose gap. force and membrane currents were recorded during voltage clamp. after a 20-s rest, 10 clamps from a holding potential of -40 to 0 mv at 1.0 hz were given. this was followed by a test clamp (called 1) of a varied duration and amplitude and two more test clamps (called 2 and 3) as during the priming period. peak force of contraction 1 (f1) was independent of clamp duration from 2s to about 100 ms but ... | 1992 | 1442125 |
| an angiographic method for in vivo study of arteries of the circle of willis in small animals. | an x-ray imaging technique designed to allow sequential diameter measurements of the cerebral vessels in intact, anesthetized small animals under relatively physiological conditions is described. the ferret and the rabbit were chosen as potentially useful animal models for studying the cerebrovascular system because of the advantageous anatomic characteristics of these relatively small species. a commercially available and relatively inexpensive x-ray imaging system with a small focal spot provi ... | 1992 | 1443212 |
| the effects of intraluminal and extraluminal drug application on secretion and smooth muscle tone in the ferret liquid-filled trachea in vitro. | with the ferret liquid-filled trachea in vitro, intraluminal methacholine (mch), phenylephrine (pe) and histamine (hist) increased smooth muscle tone and salbutamol (salb) decreased tone. lysozyme output was increased by intraluminal mch and pe. albumin transport into the lumen was not altered by intraluminal hist, salb or pe. the concentration-response curves for smooth muscle contraction and for lysozyme output to extraluminal mch lay to the left of those for intraluminal mch. indomethacin shi ... | 1992 | 1446138 |
| an in vivo preparation for measurement of plasma protein and lysozyme output in the ferret tracheal lumen. | an in-vivo ferret tracheal preparation has been developed to study the appearance in the liquid-filled trachea of fluorescein-labelled plasma proteins (flp) and of lysozyme from submucosal gland serous cells. in order to investigate the influence of nervous activity on the appearance of flp and lysozyme in the tracheal lumen, the effects of intraluminal bradykinin (an inflammatory mediator and sensory nerve stimulant), intraluminal capsaicin (a stimulant of c-fibres) and electrical stimulation o ... | 1992 | 1446140 |
| development of mucociliary transport in the postnatal ferret trachea. | little is known of the developmental aspects of mucociliary transport. previous studies have documented that newborn ferret trachea has very few ciliated cells but numerous immature secretory cells in the epithelium and only rudimentary submucosal glands. rapid and complete maturation occurs in the first postnatal month. this study examines mucociliary transport during this period of rapid maturation. we made direct observations of particle movement across the epithelium of ferret tracheas. no m ... | 1992 | 1447097 |
| effect of immunisation against vasoactive intestinal polypeptide on gastric corpus tone and motility in the ferret. | the role of vasoactive intestinal polypeptide in the control of gastric corpus tone and motility was investigated using auto-antibodies to neutralise endogenous vasoactive intestinal polypeptide. six ferrets were immunised with vasoactive intestinal polypeptide thyroglobulin conjugate in freund's complete adjuvant which resulted in a significant increase in plasma vasoactive intestinal polypeptide binding activity compared with unimmunised control animals. in acute experiments the level of spont ... | 1992 | 1452070 |
| discovery of a well-absorbed, efficacious renin inhibitor, a-74273. | the development of orally active renin inhibitors has been plagued by limited bioavailability in animals and humans. a-74273 is a novel, potent nonpeptide inhibitor of human renin (ic50 = 3.1 nm). this compound was absorbed into the portal and systemic circulations of anesthetized rats, ferrets, monkeys, and dogs after intraduodenal dosing. this favorable pattern also was observed after oral dosing in conscious animals, except in monkeys. hepatic extraction of a-74273 was more efficient in rats ... | 1992 | 1452292 |
| pharmacology of the 5-hydroxytryptamine-induced depolarization of the ferret vagus nerve in vitro. | grease-gap recordings revealed that 5-hydroxytryptamine (5-ht) depolarized the ferret vagus nerve (pec50 = 4.9). this response was mimicked by 2-methyl-5-ht and 1-phenylbiguanide, but not by 5-carboxamidotryptamine. paroxetine (1 microm) or ketamine (10 microm) did not potentiate the response. ketanserin (1 microm) did not reduce the depolarization, but four 5-ht3 receptor antagonists did. it is concluded that 5-ht depolarizes the ferret vagus nerve via 5-ht3 receptors, but these receptors may d ... | 1992 | 1459188 |
| neuropharmacology of emesis in relation to clinical response. | 5-ht3 receptor antagonists such as ondansetron, granisetron, ics205-930 and zacopride are highly effective in the ferret, cat or dog to prevent emesis caused by cisplatin and other chemotherapeutic agents, and radiation treatment. the anti-emetic effects may be mediated centrally in the area postrema and associated structures of the emetic reflex such as the nucleus tractus solitarius, which have a very high density of 5-ht3 receptors. additional sites of action may be found on the 5-ht3 recepto ... | 1992 | 1467196 |
| metabolic changes during ischaemia and their role in contractile failure in isolated ferret hearts. | 1. the effects of global ischaemia on phosphorus metabolites, intracellular ph (phi) and developed pressure were measured in isolated whole ferret hearts using 31p nuclear magnetic resonance (nmr) spectroscopy. 2. brief (10 min) periods of global ischaemia reduced left ventricular developed pressure (lvdp) to undetectable levels. this fall in lvdp was accompanied by a fall in the intracellular concentration of phosphocreatine (pcr) and increases in the concentrations of inorganic phosphate (pi) ... | 1992 | 1474498 |
| age-related differences in vascular effects of pentoxifylline in isolated perfused ferret lungs. | we have determined the magnitude and sites of action of pentoxifylline (ptx), a methylxanthine derivative, in the adult and 3- to 4-week old ferret pulmonary circulation. lungs of 8 ferrets, four 3- to 4-week-old and 4 adult, were isolated and perfused with blood. during perfusion, blood flow was kept constant, as were airway and left atrial pressures (6 and 8 cm h2o respectively, zone 3 conditions). in all lungs, pulmonary artery pressure was measured continuously and the circulation was partit ... | 1992 | 1483354 |