| cloning and characterization of a lung-specific cdna corresponding to the gamma chain of hepatic fibrinogen. | the gene (gamma fbg) encoding the fibrinogen gamma chain (gamma fbg) has been shown to exhibit both tissue-specific and ubiquitous expression. to confirm the identity of the gamma fbg transcripts expressed in extrahepatic tissue, lung tissue was chosen as a model of extrahepatic gamma fbg gene expression. a ferret lung cdna clone bank was constructed in lambda gt11 and several positive plaques were isolated using cross-species hybridization with the rat gamma fbg cdna. sequence data of the longe ... | 1995 | 8566791 |
| biarylcarboxylic acids and -amides: inhibition of phosphodiesterase type iv versus [3h]rolipram binding activity and their relationship to emetic behavior in the ferret. | in addition to having desirable inhibitory effects on inflammation, anaphylaxis, and smooth muscle contraction, pde-iv inhibitors also produce undesirable side effects including nausea and vomiting. in general, compounds that inhibit pde-iv also potently displace [3h]rolipram from a high-affinity binding site in rat cortex. while this binding site has not been identified, it has been proposed to be an allosteric binding site on the pde-iv enzyme. preliminary studies have suggested that the emeti ... | 1996 | 8568798 |
| relationships between the nuclear membrane, nuclear pore complexes, and organelles in the type ii pneumocyte. | functional relationships among organelles of the type ii cell are suggested based upon the proximity of organelles to specialized areas of the plasma- and nuclear membranes. in a two-dimensional morphometric analysis of the profiles of organelles in type ii cells of the ferret and rat (and beagle dog), lamellar bodies were more likely to be located near the nuclear membrane than at the alveolar space (where exocytosis occurs). the size of lamellar body profiles was not correlated with distance f ... | 1995 | 8578555 |
| receptor specificity of influenza virus influences severity of illness in ferrets. | weanling ferrets were inoculated intranasally with either wild-type or receptor-variant clones of influenza a/memphis/102/72 to determine if changes in receptor specificity influence virulence of influenza virus infection. over the 5 days after inoculation, receptor-variant inoculated ferrets had a lower mean elevation in body temperature, greater weight gain and less sneezing than the wild-type group. influenza virus was recovered from the lungs of fewer receptor-variant infected ferrets (5/12 ... | 1995 | 8578828 |
| the ferret as a small animal model with bmu-based remodeling for skeletal research. | the need exists for a small animal model with bone metabolic unit (bmu)-based remodeling to mimic the bone loss found in postmenopausal women. the purpose of this investigation was to evaluate the ferret as a potential model for skeletal research. specifically, we determined whether the ferret: 1) exhibits evidence of bmu-remodeling, 2) has a skeletal response to parathyroid hormone (pth) similar to other remodeling species, and 3) loses bone in response to reduced estrogen levels. methods: usin ... | 1995 | 8579916 |
| animal models of cortical porosity. | increased cortical porosity (ct.po) has been observed as a consequence of aging, disease (hyperparathyroidism, osteoporosis), and pharmacologic intervention (thyroid hormone, fluoride, parathyroid hormone, prostaglandins). whether this is permanent or transient in humans has not been established nor has the impact of ct.po on bone strength or fracture incidence been determined. there is a need to understand the causes and consequences of increased ct.po and how it relates to disease states and o ... | 1995 | 8579932 |
| gg167 (4-guanidino-2,4-dideoxy-2,3-dehydro-n-acetylneuraminic acid) is a potent inhibitor of influenza virus in ferrets. | gg167 (4-guanidino-2,4-dideoxy-2,3-dehydro-n-acetylneuraminic acid) is a novel viral neuraminidase (sialidase) inhibitor which, following intranasal administration in ferrets, is at least 100 to 1,000 times more effective than ribavirin and amantadine against influenza a and b viruses. it retains its activity even when treatments are delayed until 24 h postinfection and has no effect on the serum antibody response to infection. | 1995 | 8585752 |
| pathogenicity of morbilliviruses for terrestrial carnivores. | many different species of the order carnivora are susceptible to canine distemper and the mortality rate varies greatly between species. ailuridae, canidae, hyaenidae, mustelidae, procyonidae, ursidae, viverridae and now felidae have been reported to be susceptible to canine distemper virus infection. although distemper outbreaks in dogs, fur farms and in zoo carnivores have been greatly reduced in recent years due to vaccination, there are still regular outbreaks in free-living carnivores. unex ... | 1995 | 8588312 |
| transforming growth factor-alpha immunoreactivity during induced hair follicle growth cycles in sheep and ferrets. | transforming growth factor-alpha (tgf-alpha) has been associated with cell proliferation of keratinocytes and implicated in hair growth. we therefore examined changes in the immunocytochemical localization of tgf-alpha and cell proliferation markers in the skin of two unrelated species in which hair cycles could be induced, to elucidate the role of this growth factor in the control of fiber growth. skin was collected from melatonin-treated ferrets (mustela putorius furo), untreated romney sheep ... | 1996 | 8601697 |
| a systematic map of direction preference in primary visual cortex. | neurons in the primary visual cortex respond selectively to the orientation of edges and their direction of motion. orientation preference is mapped in a systematic fashion across the cortical surface, such that neurons in adjacent columns have similar but slightly shifted preferred orientations. microelectrode studies have suggested that direction preference is also arranged in a systematic fashion, but exactly how this response property is mapped remains unclear. here we show by optical imagin ... | 1996 | 8602218 |
| search for extrapulmonary pneumocystis carinii in an animal model. | pneumocystis carinii-infected immunosuppressed ferrets and rats were searched for p. carinii cysts and trophozoites in extrapulmonary organs, including the heart, liver, stomach, kidney, and spleen. foci of p. carinii were found in the liver or kidney of 4 (10%) of 40 ferrets but in no extrapulmonary sites of 30 rats with p. carinii pneumonitis. attempts to identify p. carinii from immunosuppressed rat or ferret blood or propagate the organism intraorbitally in immunosuppressed rats were unsucce ... | 1996 | 8604119 |
| seasonal variation in the phenotype of adult ferret (mustela putorius furo) cremaster muscle. | using immunocytochemistry, electrophoresis and immunoblotting, we studied the expression of fast and slow myosin heavy chain isoforms in adult ferret muscles during quiescent and breeding periods. adult cremaster muscle expressed slow and fast myosin heavy chain in relatively similar amounts during the quiescent period. during the breeding period, the expression of slow myosin heavy chain, i, significantly decreased, and fast myosin heavy chain ii, was predominant. no alteration of the mhc patte ... | 1996 | 8608822 |
| exposure to environmental tobacco smoke results in an increased production of (+)-anti-benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide in juvenile ferret lung homogenates. | six-week-old ferrets were exposed head-only to clean air or environmental tobacco smoke (ets) at an average particulate concentration of 38 +/- 13 mg/m3 for 2 h/d, 5 d/wk for up to 15 wk. twenty four hours after last exposure, the ferrets were sacrificed and the metabolism of benzo[a]pyrene and (-)-7r-trans-benzo[a]pyrene-7,8-dihydrodiol was studied in lung homogenates. the results show that after ets exposure total metabolism of benzo[a]pyrene, measured by the accumulation of hexane nonextracta ... | 1996 | 8614021 |
| pharmacology of l-744,453, a novel nonpeptidyl endothelin antagonist. | l-744,453 ((+/-)3-[4-(1-carboxy-1-(3,4-methylenedioxyphenyl)methoxy)-3,5-diprop ylphenyl methyl]-3h-imidazo[4,5-c]pyridine) is an endothelin (et) receptor antagonist from a new structural class, the dipropyl-alpha-phenoxyphenylacetic acid derivatives. l-744,453 competitively and reversibly inhibits [125i]-et-1 binding to chinese hamster ovary cells expressing cloned human et receptors (k(i)s: het(a)=4.3 nm; het(b)=232 nm), and is selective for endothelin receptors compared to other peptide recep ... | 1996 | 8614266 |
| effect of ethanol on the excitability of the inferior olive in decerebrate ferret. | climbing fibers, which originate in the inferior olive and project to purkinje cells and golgi cells in the cerebral cortex, were activated at low (0.4-hz) and high (4-hz) frequencies by periorbital stimulation in decerebrate ferrets. climbing fiber responses were recorded as field potentials from the c3 zone of the cerebellar surface. when periorbital stimulation was applied at high frequency, the climbing fiber responses became strongly depressed within a few seconds. it has previously been sh ... | 1996 | 8627556 |
| granular cell tumour in the central nervous system of a ferret (mustela putorius furo). | | 1996 | 8629332 |
| clusters of lymphoma in ferrets. | cluster outbreaks of lymphoma and leukemia have been associated with viral infections in many species including humans, cattle, and cats. this study describes epidemiological, clinical, and pathological features of cluster outbreaks of lymphoma in multiferret households and examines and compares the aleutian disease virus (adv) and feline leukemia virus (felv) status of cases, ferrets at risk, and controls. three ferret groups with 21 cases of histologically diagnosed lymphoma (12.6% cumulative ... | 1996 | 8630683 |
| the crystalline form of carotenes and the food matrix in carrot root decrease the relative bioavailability of beta- and alpha-carotene in the ferret model. | the objective of this study was to investigate the relative bioavailability (bv) of beta-carotene (bc) and alpha-carotene (ac) from different extracts of carrots utilizing the ferret model. | 1996 | 8632121 |
| helicobacter mustelae-associated hypergastrinemia in ferrets (mustela putorius furo). | to determine whether ferrets naturally infected with helicobacter mustelae were hypergastrinemic, compared with ferrets that were specific-pathogen-free (spf) for h mustelae. | 1996 | 8633798 |
| in situ hybridization reveals extensive diversity of k+ channel mrna in isolated ferret cardiac myocytes. | the molecular basis of k+ currents that generate repolarization in the heart is uncertain. in part, this reflects the similar functional properties different k+ channel clones display when heterologously expressed, in addition to the molecular diversity of the voltage-gated k+ channel family. to determine the identity, regional distribution, and cellular distribution of voltage-sensitive k+ channel mrna subunits expressed in ferret heart, we used fluorescent labeled oligonucleotide probes to per ... | 1996 | 8635239 |
| clinical and pathologic findings in ferrets with lymphoma: 60 cases (1982-1994). | to examine clinical and pathologic findings in 60 ferrets with lymphoma. | 1996 | 8635973 |
| bay k 8644 depresses excitation-contraction coupling in cardiac muscle. | we determined the effect of the dihydropyridine l-type ca channel agonist bay k 8644 (bay) on excitation-contraction (e-c) coupling in isolated ferret ventricular myocytes using whole cell voltage clamp. the sarcoplasmic reticulum (sr) ca load during the test pulses, assessed by caffeine-induced contractures, was similar in the presence and absence of bay, with extracellular ca concentration lowered from 3 to 1 mm in bay. the relationship between l-type ca current (ica) and contraction was asses ... | 1996 | 8638669 |
| a ferret model of electrical-induction of arterial thrombosis that is sensitive to aspirin. | an experimental model of acute thrombosis was developed in pentobarbital- anesthetized ferrets. a 10-min anodal electrical stimulation of 1 ma was delivered to the external surface of the carotid artery while measuring carotid blood flow (cbf). this produced an occlusive thrombus in all vehicle-treated ferrets within 41 +/- 3 min with an average weight of 8 +/- 1 mg (n = 7). these thrombi were enriched in both platelets and fibrin and were adherent at the site of transmural vascular injury as de ... | 1996 | 8645878 |
| na-ca exchange and ca fluxes during contraction and relaxation in mammalian ventricular muscle. | there are four cellular ca transport systems which compete to remove ca from the myoplasm in mammalian ventricular myocytes. these are 1) the sr ca-atpase, 2) the sarcolemmal na-ca exchange, 3) the sarcolemmal ca-atpase and 4) the mitochondrial ca uniporter. using multiple experimental approaches we have evaluated the dynamic interaction of these systems during the normal cardiac contraction-relaxation cycle. the sr ca-atpase and na-ca exchange are clearly the most important, quantitatively; how ... | 1996 | 8659859 |
| changing patterns of spontaneous bursting activity of on and off retinal ganglion cells during development. | in adult ferrets, retinal ganglion cells (rgcs) responsive to increased (on) or decreased (off) illumination convey information to different cellular layers of the dorsal lateral geniculate nucleus (dlgn). these dlgn sublaminae emerge during development when rgcs are found to undergo correlated spontaneous bursting activity. using ca2+ imaging and intracellular dye-filling techniques, we demonstrate here that in ferret neonates, morphologically identified on and off beta rgcs have similar burst ... | 1996 | 8663985 |
| [ultrastructural analysis of pathological changes in ferrets with experimental canine distemper]. | morphologic study of the lungs, liver, spleen, and kidneys of ferrets infected with canine distemper virus has been carried out. electron microscopy revealed virus reproduction in bronchial epithelial cells, types i and ii alveolocytes, bile duct epitheliocytes, and hepatocytes. mononuclear phagocyte system cells infected with the virus were found in all the examined organs. the most expressed pathological changes were observed in the lungs. | 1996 | 8669139 |
| development of horizontal projections in layer 2/3 of ferret visual cortex. | pyramidal cells in layer 2/3 of cat striate cortex extend long axons that form clustered projections linking iso-orientation columns. using extracellular biocytin injections in brain slices, the formation of these projections was examined in the ferret to determine whether horizontal projections exhibit similar patterns of development in the ferret and the cat, and to relate the time course of horizontal projection formation to the onset of patterned visual experience and orientation selectivity ... | 1996 | 8670648 |
| developmental expression patterns of cftr in ferret tracheal surface airway and submucosal gland epithelia. | submucosal glands are a major site of cystic fibrosis transmembrane conductance regulator (cftr) expression in the human airway and may play an important role in the pathogenesis of cystic fibrosis. in humans, strategies for gene targeting to submucosal glands will likely be dependent on in utero gene transfer to submucosal gland progenitors because of the inaccessibility of these regions from the fully developed airway. however, little is known about the ontogeny of cftr gene expression in deve ... | 1996 | 8679216 |
| calcium compartments in vascular smooth muscle cells as detected by aequorin signal. | 1. to examine whether cytosolic ca2+ in smooth muscle cells distributes evenly, cytosolic ca2+ levels were measured with two different ca2+ indicators in the ferret isolated portal vein; a fluorescent indicator, fura-pe3, that shows the average ca2+ level, and a photoprotein, aequorin, that preferentially shows a high ca2+ compartment. 2. a noradrenaline (10 microm)-induced sustained contraction was associated with a sustained increase in the fura-pe3 signal, or a transient increase followed by ... | 1995 | 8680735 |
| the interaction of dexamethasone with ondansetron on drug-induced emesis in the ferret. | the potential of dexamethasone (0.5-20 mg/kg i.p.) to antagonize the emesis induced by cisplatin (10 mg/kg i.v.), apomorphine (0.25 mg/kg s.c.), morphine (0.5 mg/kg s.c.) and copper sulphate (100 mg/kg intragastric) was investigated alone and in combination with ondansetron in the ferret. there was a trend for dexamethasone 0.1-5 mg/kg to reduce cisplatin-induced emesis and for 0.05-2.5 mg/kg to delay the onset of apomorphine-induced emesis but doses of dexamethasone up to 20 mg/kg were without ... | 1996 | 8684601 |
| mechanisms of chemotherapy/radiotherapy-induced emesis in animal models. | animal models of chemotherapy/radiotherapy-induced emesis successfully predicted the clinical efficacy of the 5-ht3 receptor antagonists for the control of acute emesis. further studies in animals have provided valuable information relating to the pathophysiology of emesis and the mechanism of action of 5-ht3 receptor antagonists. these agents inhibit emesis by blocking the action of 5-ht at 5-ht3 receptors on the vagus nerve in the gastrointestinal tract and in the hindbrain vomiting system. 5- ... | 1996 | 8692557 |
| yeast infection in ferrets. | | 1995 | 8693680 |
| surface properties of helicobacter mustelae and ferret gastrointestinal mucosa. | helicobacter mustelae is a gastric pathogen in ferrets that adheres to epithelial cells both in vitro and in vivo. in this study, the authors examine the role of surface hydrophobic properties in the adhesion of these organisms to eukaryotic cell surfaces. the surface properties of six h. mustelae strains were characterized by hydrophobic interaction chromatography (hic), salt aggregation testing (sat) and contact-angle measurement by axisymmetric drop-shape analysis (adsa). contact angles in mu ... | 1996 | 8697675 |
| multiple splenic myelolipomas in a ferret (mustela putorius furo). | | 1996 | 8699802 |
| the pharmacology of gr203040, a novel, potent and selective non-peptide tachykinin nk1 receptor antagonist. | 1. the in vitro and in vivo pharmacology of gr203040 ((2s, 3s)-2-methoxy-5-tetrazol-1-yl-benzyl-(2-phenyl-piperidin-3-y l)-amine), a novel, highly potent and selective non-peptide tachykinin nk1 receptor antagonist, was investigated in the present study. 2. gr203040 potently inhibited [3h]-substance p binding to human nk1 receptors expressed in chinese hamster ovary (cho) and u373 mg astrocytoma cells, and nk1 receptors in ferret and gerbil cortex (pki values of 10.3, 10.5, 10.1 and 10.1 respect ... | 1995 | 8719789 |
| the broad-spectrum anti-emetic activity of the novel non-peptide tachykinin nk1 receptor antagonist gr203040. | 1. following our earlier observations that the tachykinin nk1 receptor antagonist cp-99,994 is an effective anti-emetic in ferrets, we have examined the anti-emetic effects of a more potent and novel nk1 receptor antagonist, gr203040, against various emetic stimuli in the ferret, dog and house musk shrew (suncus murinus). 2. in ferrets, gr203040 (0.1 mg kg-1 s.c. or i.v.) is effective against emesis induced by radiation, cisplatin, cyclophosphamide, copper sulphate, ipecacuanha or morphine. 3. i ... | 1995 | 8719790 |
| evidence for a projection from the perireticular thalamic nucleus to the dorsal thalamus in the adult rat and ferret. | during early development, the perireticular thalamic nucleus is very large (i.e. has many cells) and has a strong projection to the dorsal thalamus and to the cerebral neocortex. by adulthood, the nucleus has much reduced in size and only a few cells remain. it is not clear whether these perireticular cells that remain into adulthood maintain their connections with the dorsal thalamus and with the neocortex. this study examines this issue by injecting neuronal tracers into various nuclei of the ... | 1995 | 8719817 |
| assessment of humoral immune response in mink (mustela vison): antibody production and detection. | a method for investigating the humoral immune response in mink (mustela vison) was developed between october 1993 and march 1994. protein a, 1:8000 dilution, had a high affinity for mink immunoglobulin, while anti-ferret (mustela putorius) antibody, 1:200 dilution, had a weaker affinity. four adult mink were immunized with a hapten, dinitrophenol (dnp), conjugated to a large carrier protein, keyhole limpet hemocyanin (klh), and received two boosters at 3-week intervals. this provoked a strong t- ... | 1996 | 8722279 |
| ex-vivo treatment of gastric helicobacter infection by photodynamic therapy. | attempts to develop pdt for eradication of helicobacter infection have only been successful in vitro. we have investigated the effect of topical sensitization (except ala) of helicobacter mustelae on explanted ferret gastric mucosa using one of five sensitizers (methylene blue (mb), toluidine blue o (tbo), phthalocyanine, haematoporphyrin derivative and 5-aminolavulinic acid), followed by irradiation with an appropriately tuned copper vapour pumped dye laser. a 90% reduction in counts of bacteri ... | 1996 | 8725054 |
| in vivo biosynthesis of retinoic acid from beta-carotene involves and excentric cleavage pathway in ferret intestine. | this study was done to determine whether retinoic acid can be produced by excentric cleavage of beta-carotene in vivo. by using an inhibitor of retinaldehyde oxidation, citral, either retinaldehyde or beta-carotene was incorporated in a micellar solution and perfused through the upper portion of small intestine of ferrets. after 2 h perfusion of 1 microm retinaldehyde, retinoic acid rose in portal blood (+3.5 +/- 1.3 nmol/l) and was detected in the intestinal mucosa (30 +/- 2 pmol/g). when citra ... | 1996 | 8728312 |
| adherence of helicobacter pylori. | helicobacter pylori infects only gastric type epithelium, to which it adheres closely and forms attaching-effacing lesions. similar lesions are also seen in ferrets infected with helicobacter mustelae, the only other host in which peptic ulcer occurs during the course of infection. these observations imply a specific interaction between bacterial adhesin(s) and host receptor(s). they account for the adherence of h. pylori to the gastric epithelium and suggest that adherence is an important virul ... | 1996 | 8730255 |
| an interaction of ondansetron and dexamethasone antagonizing cisplatin-induced acute and delayed emesis in the ferret. | 1. cisplatin, 5 mg kg-1, i.p., administered as a single treatment, induced an acute (day 1) and delayed (days 2 and 3) emetic response in the ferret that was used to investigate the potential anti-emetic activity of ondansetron and dexamethasone and their interaction over a three day period. 2. ondansetron, 1 mg kg-1, i.p., administered three times per day in two experiments, antagonized significantly the retching and vomiting that occurred on days 1 and 2 by 60-76 and 73-84%. on the third day o ... | 1996 | 8735616 |
| substance p hyperpolarizes vagal sensory neurones of the ferret. | 1. intracellular recordings were made in intact and in acutely dissociated vagal afferent neurones (nodose ganglion cells) of the ferret to investigate the effects of substance p(sp). 2. in current-clamp recordings, sp (100 nm) applied by superfusion hyperpolarized the membrane potential (7 +/- 0.7 mv; mean +/- s.e.m.; n = 105) and decreased the input resistance in 80% of the neurones. with voltage-clamp recording, sp produced an outward current of 3 +/- 0.2 na (n = 10). 3. the sp current was co ... | 1996 | 8735701 |
| the temporal pattern of mating-induced immediate-early gene product immunoreactivity in lhrh and non-lhrh neurons of the estrous ferret forebrain. | the mating-induced preovulatory surge of luteinizing hormone (lh) lasts for at least 12 h in the female ferret. this prolonged increase in circulating lh is presumably accompanied by a corresponding elevation in the activity and output of luteinizing hormone-releasing hormone (lhrh) neurons projecting to the hypothalamic-hypophyseal portal blood vessels and adenohypophysis. we used the protein products of the immediate early genes (iegs) c-fos, and c-jun as markers of neural activation in order ... | 1996 | 8736434 |
| effects of moderate hypothermia on baroreflex and pulmonary chemoreflex heart rate response in decerebrate ferrets. | the effects on the baroreceptor reflexes and pulmonary reflexes of moderate immersion hypothermia (core temperature, 30.2 +/- 0.07 degrees c) have been investigated in the decerebrate ferret. baroreflex sensitivity was estimated from the relationship between change in cardiac interval and change in systolic blood pressure following i.v. bolus injection of phenylephrine. the responses to phenylephrine in ferrets were best fitted by two linear slopes with an initial shallow slope, a, followed by a ... | 1996 | 8737075 |
| modulation of vagal actions on heart rate produced by inhibition of nitric oxide synthase in the anaesthetized ferret. | we have examined a possible role for nitric oxide in the efferent vagal control of heart rate of the anaesthetized ferret, using stimulation of the motor fibres of the right vagus at supramaximal intensities and increasing frequencies. propranolol was used to block beta-adrenergic actions on the heart. l-name (50-100 mg i.v.) significantly reduced the bradycardia induced by vagal stimulation at all frequencies tested (1-15 hz); subsequent infusion of l-arginine (100-200 mg i.v.) restored the vag ... | 1996 | 8737087 |
| pharmacological properties of quinoxaline derivatives as a new class of 5-ht3 receptor antagonists. | the pharmacological profile of five quinoxaline derivatives, a new class of 5ht3 receptor antagonists, is reported in the present study. all of the new compounds antagonized the effect of the selective 5-ht3 receptor agonist 2-methyl-5-ht in the isolated longitudinal muscle-myenteric plexus preparation (lmmp) of guinea-pig ileum. one of them, vc-605) was approximately three orders of magnitude more potent than ondansetron. in binding studies to 5-ht3 receptors from rat cerebral cortex membranes ... | 1996 | 8740088 |
| estrogenic control of preoptic area development in a carnivore, the ferret. | 1. evidence is reviewed which shows that a sexually dimorphic nucleus located in the dorsomedial portion of the male ferret's preoptic area/anterior hypothalamus (poa/ah), called the male nucleus of the poa/ah (mn-poa/ah), develops during fetal life in response to the action of estradiol, which is formed directly in the nervous system from circulating testosterone over the final quarter of a 41-day gestation. 2. results are summarized which establish that neurons which make up the mn-poa/ah are ... | 1996 | 8743964 |
| activation and inactivation kinetics of an e-4031-sensitive current from single ferret atrial myocytes. | ferret atrial myocytes can display an e-4031-sensitive current (ikr) that is similar to that previously described for guinea pig cardiac myocytes. we examined the ferret atrial ikr as the e-4031-sensitive component of current using the amphotericin b perforated patch-clamp technique. steady-state ikr during depolarizing pulses showed characteristic inward rectification. activation time constants during a single pulse were voltage dependent, consistent with previous studies. however, for potentia ... | 1996 | 8744308 |
| possible functional linkage between the cardiac dihydropyridine and ryanodine receptor: acceleration of rest decay by bay k 8644. | the effect of the dihydropyridine l-type ca chanel agonist bay k 8644 on post-rest contractions in ferret ventricular muscle and isolated myocytes was investigated. bay k 8644 was shown to abolish rest potentiation and greatly accelerate rest decay. the post-rest contraction suppressed by bay k 8644 was accompanied by action potentials of large amplitude and longer duration, but voltage-clamp measurements showed that this suppression was not due to a supra-optimal ica trigger. caffeine-induced c ... | 1996 | 8745216 |
| liposarcoma arising from the mandibular bone marrow in a ferret. | | 1995 | 8748452 |
| neural integration of jejunal motility and ion transport in nematode-infected ferrets. | jejunal motility measured manometrically and coupled fluctuations in electrogenic ion transport measured as transmural potential differences (pd) were simultaneously studied in ferrets infected with enteric stages of the parasitic nematode, trichinella spiralis. vagotomy in uninfected ferrets abolished jejunal motility clusters and associated pd oscillations. conversely, in infected ferrets on days 8-12 postinfection (pi), vagotomy did not abolish jejunal motility and pd. calculated motility ind ... | 1996 | 8760106 |
| effect of vagal and splanchnic nerve section on fos expression in ferret brain stem after emetic stimuli. | previous studies have demonstrated that intraduodenal hypertonic saline (ihs) induces dense fos expression within two regions of the ferret dorsal vagal complex (dvc): the area postrema (ap) and the medial subnucleus of the nucleus of the solitary tract (mn). the aims of the present experiments were to determine the peripheral pathways involved in excitation of dvc neurons after ihs and the relative importance of mn and ap excitation in the emetic response to this stimulus. the emetic response a ... | 1996 | 8760225 |
| intracellular ph and intrinsic h+ buffering capacity in normal and hypertrophied right ventricle of ferret heart. | to answer the questions: (a) what is the effect of hypertrophy on the intracellular ph (phi) and buffering power of cardiac muscle, and (b) how does hypertrophy affect the ability of cardiac muscle to recover from intracellular acidosis induced by hypoxia. | 1996 | 8763402 |
| angiotensin ii stimulates sodium-dependent proton extrusion in perfused ferret heart. | the na+/h+ antiport and na(+)-hco3- coinflux carrier contribute to recovery from intracellular acidosis in cardiac tissue. the effects of angiotensin ii (10(-12)-10(-6) m) on h+ fluxes after intracellular acid loading and during reperfusion after myocardial ischemia have been investigated in the isovolumic, langendorff-perfused ferret heart. intracellular ph (phi) was estimated using 31p nuclear magnetic resonance (nmr) spectroscopy from the chemical shift of intracellular deoxyglucose-6-phospha ... | 1996 | 8764151 |
| length-dependent activation in intact ferret hearts: study of steady-state ca(2+)-stress-strain interrelations. | we examined the steady-state stress-strain relationships and the steady-state stress-intracellular calcium concentration ([ca2+]i) relationship in intact ferret hearts and compared these to previously published analogous relationships in skinned and intact muscle. langendorff-perfused ferret hearts were treated with ryanodine and tetanized by rapid stimulation to create steady-state conditions. [ca2+]i was measured concurrently by macroinjected aequorin. over a range of volumes corresponding to ... | 1996 | 8764242 |
| epsilon-isoenzyme of protein kinase c induces a ca(2+)-independent contraction in vascular smooth muscle. | we provide here the first direct evidence for in situ functional specificity of protein kinase c (pkc)-epsilon as a regulator of smooth muscle contractility. pkc is known to cause a ca(2+)-independent contraction of ferret aortic smooth muscle, and the expression of two ca(2+)-independent pkc isoenzymes, epsilon and zeta, has been demonstrated in this tissue. to test directly the hypothesis that one of these isoenzymes regulates contractility, constitutively active forms of pkc-epsilon and pkc-z ... | 1996 | 8769999 |
| pcr detection of colonization by helicobacter pylori in conventional, euthymic mice based on the 16s ribosomal gene sequence. | many animal models of helicobacter infection have been described, including infection in rhesus monkeys, ferrets, gnotobiotic piglets, and mice. these animal models utilize a combination of detection methods, including culture, urease testing, and histopathology, all of which may be unreliable, insensitive, or labor-intensive. development of new animal models of helicobacter pylori requires new methods of detection with increased sensitivity and specificity. we have developed sensitive and speci ... | 1996 | 8770506 |
| diversity of host species and strains of pneumocystis carinii is based on rrna sequences. | we have amplified by pcr pneumocystis carinii cytoplasmic small-subunit rrna (variously referred to as 16s-like or 18s-like rrna) genes from dna extracted from bronchoalveolar lavage and induced sputum specimens from patients positive for p. carinii and from infected ferret lung tissue. the amplification products were cloned into puc18, and individual clones were sequenced. comparison of the determined sequences with each other and with published rat and partial human p.carinii small-subunit rrn ... | 1996 | 8770515 |
| involvement of dopamine d3 receptors in the area postrema in r(+)-7-oh-dpat-induced emesis in the ferret. | we investigated the possible involvement of dopamine d3 receptors in r(+)-7-hydroxy-2-(n,n-di-n-propylamino)tetraline (r(+)-7-oh-dpat)-induced emesis in the ferret. the r(+)enantiomer of 7-oh-dpat (0.03-1 mg/kg, s.c.) caused emesis in a dose-dependent manner, whereas the s(-)enantiomer, even at 1 mg/kg s.c. failed to induce emesis. quinpirole (0.1-1.0 mg/kg) and apomorphine (0.3 mg/kg, s.c. only) also elicited an emetic response. s(-)-eticlopride, which has a high affinity for the dopamine d3 re ... | 1996 | 8773458 |
| identification of a dna segment in ferret aleutian disease virus similar to a hypervariable capsid region of mink aleutian disease parvovirus. | a 401bp dna fragment of ferret aleutian disease virus (adv) was amplified using pcr primers spanning a hypervariable region of mink adv capsid sequence. the amplified fragment was 88-89% homologous to the same region of previously known sequence of three different strains of mink adv, however, as low as 54% homology was observed when compared with a 39bp segment known as hypervariable region. within the predicted 13 amino acid hypervariable region, the ferret adv sequence differed at 6 positions ... | 1996 | 8774691 |
| cholinergic stimulation modulates negative inotropic effect of cocaine on ferret ventricular myocardium. | we tested the hypothesis that the negative inotropic effect (nie) of cocaine is mediated, at least in part, by cholinergic stimulation and can be correlated with the degree of adenosine 3',5'-cyclic monophosphate (camp) dependency of the inotropic state. cardiac myocytes were isolated from left ventricles of ferrets and loaded with the fluorescent ca2+ indicator indo 1. cells were placed in physiological solution containing 2.0 mm ca2+ and stimulated at 0.5 hz and 30 degrees c. cocaine decreased ... | 1996 | 8779845 |
| abolition of spindle oscillations by serotonin and norepinephrine in the ferret lateral geniculate and perigeniculate nuclei in vitro. | the transition from sleep to waking is associated with the abolition of spindle waves in thalamocortical neurons and the gabaergic cells of the thalamic reticular/perigeniculate nuclei. we tested the possibility that norepinephrine (ne) and serotonin (5-ht) may abolish spindle wave generation through an enhancement of the hyperpolarization-activated cation current ih in thalamocortical neurons. local application of agents known to enhance ih, including 5-ht, ne, the adenylyl cyclase activator, f ... | 1996 | 8780654 |
| magnesium transport in magnesium-loaded ferret red blood cells. | mg efflux from ferret red blood cells is stimulated when cells are mg loaded, but the properties of efflux depend on the loading method. when cell mg content is altered using a23187, which is subsequently washed away, mg efflux is minimal until intracellular ionized [mg] ([mg2+]i) is greater than 0.9 mm, it then increases substantially with [mg2+]i. efflux from loaded cells falls as external [na] ([na]o) is reduced, and net mg influx (against an electrochemical gradient) is seen when [na]o is su ... | 1996 | 8781193 |
| effects of caffeine and cyclopiazonic acid on contractile proteins of adult and newborn ferret cardiac fibres. | ventricular trabeculae from adult and newborn ferret heart were chemically skinned by triton x-100 which disrupts all cellular membranes. in newborn preparations, maximal ca(2+)-activated tension was two times smaller than in adult fibres while ca2+ sensitivity was higher. caffeine (10 mm) and cyclopiazonic acid (100 and 200 microm) increased the ca2+ sensitivity in the two groups of preparations. the caffeine effects were more pronounced in adult than in newborn fibres while the cyclopiazonic a ... | 1996 | 8782070 |
| surface:volume relationship in cardiac myocytes studied with confocal microscopy and membrane capacitance measurements: species-dependence and developmental effects. | the quantitative analysis of the contribution of ion fluxes through membrane channels to changes of intracellular ion concentrations would benefit from the exact knowledge of the cell volume. it would allow direct correlation of ionic current measurements with simultaneous measurements of ion concentrations in individual cells. because of various limitations of conventional light microscopy a simple method for accurate cell volume determination is lacking. we have combined the optical sectioning ... | 1996 | 8785306 |
| tension-dependent changes of the intracellular ca2+ transients in ferret ventricular muscles. | 1. we measured the change in intracellular ca2+ transients, using aequorin, in response to muscle length change during twitch contraction in ferret ventricular muscles. 2. intracellular ca2+ concentration ([ca2+]i) was transiently increased when the muscle length was quickly shortened to 92% of maximum length (lmax) at various times after stimulation (this increase in [ca2+] is termed extra-ca2+). the magnitude of extra-ca2+, measured at different extracellular ca2+ concentrations ([ca2+]o), sho ... | 1995 | 8788928 |
| c-type inactivation controls recovery in a fast inactivating cardiac k+ channel (kv1.4) expressed in xenopus oocytes. | 1. a fast inactivating transient k+ current (fk1) cloned from ferret ventricle and expressed in xenopus oocytes was studied using the two-electrode voltage clamp technique. removal of the nh2-terminal domain of fk1 (fk1 delta 2-146) removed fast inactivation consistent with previous findings in kv1.4 channels. the nh2-terminal deletion mutation revealed a slow inactivation process, which matches the criteria for c-type inactivation described for shaker b channels. 2. inactivation of fk1 delta 2- ... | 1995 | 8788936 |
| intrinsic tone as potential vascular reserve in conductance and resistance vessels. | the purpose of this study was to define the degree of intrinsic tone in conductance and resistance vessels, to define the calcium dependency of intrinsic tone in these vascular preparations, and to investigate the efficacy of vasodilatory agents on the level of intrinsic tone in these vascular preparations. | 1996 | 8790050 |
| an environmentally regulated pilus-like appendage involved in campylobacter pathogenesis. | examination of strains of campylobacter jejuni, campylobacter coli, and campylobacter fetus by electron microscopy revealed that they produced peritrichous pilus-like appendages when the bacteria were grown in the presence of bile salts. various bile-salt supplements were used and it was found that deoxycholate and chenodeoxycholic acid caused a significant enhancement of pilus production and resulted in a highly aggregative phenotype. morphologically, the pili were between 4 and 7 nm in width a ... | 1996 | 8793884 |
| effects of n-methyl-d-aspartate receptor antagonists on cisplatin-induced emesis in the ferret. | glutamate may be a key transmitter in the emetic reflex arc. the present investigation focussed on the involvement of the nmda subtype of glutamate receptors in cisplatin-induced emesis. ferrets were injected with cisplatin (10 mg/kg i.v.) and either of the non-competitive nmda receptor antagonists dextromethorphan or memantine, or the competitive receptor antagonist cgs 19755. in order to determine whether there is a synergism between nmda blockers and 5-ht3 receptor antagonists, a submaximal d ... | 1996 | 8793910 |
| effect of developed tension on the time courses of ca2+ transients and tension in twitch contraction in ferret myocardium. | the aim of the study is to test the hypothesis that tension-dependent change in the affinity of cardiac troponin-c influences the time courses of ca2+ transients and tension in twitch contraction. | 1996 | 8796126 |
| nitric oxide inhibition of basal and neurogenic mucus secretion in ferret trachea in vitro. | 1. in order to examine the role of nitric oxide (no) on airway mucus secretion we studied the effects of the nitric oxide synthase (nos) inhibitor l-n(g)-monomethyl-l-arginine (l-nmma), a novel nitric oxide donor, (+/-)-(e)-ethyl-2-[(e)-hydroxyimino]-5-nitro-3-hexeneamide (fk409), and the no precursor l-arginine on basal mucus secretion in the ferret trachea in vitro in ussing chambers. we also determined the effects of these agents upon secretion induced by electrical stimulation of nerves or b ... | 1996 | 8799574 |
| a cluster of cases of juvenile mediastinal lymphoma in a ferret colony. | three cases of juvenile mediastinal lymphoma developed in a laboratory colony of ferrets. two ferrets became acutely moribund, and one was found dead with no preceding signs of illness. splenomegaly, hepatomegaly, and a large thoracic mass were the primary features in each case. all three ferrets had multiorgan metastasis of the tumor. two ferrets were tested for feline leukemia virus and aleutian disease virus with negative results. | 1996 | 8799931 |
| evaluation of plasma androgen and estrogen concentrations in ferrets with hyperadrenocorticism. | to determine plasma concentrations of steroid hormones in ferrets with hyperadrenocorticism associated with adrenocortical neoplasia or nodular hyperplasia of the adrenal gland, the effect of surgical removal of the affected adrenal gland on concentrations of these hormones, and whether any hormone concentrations could be used as a marker for the disease. | 1996 | 8800255 |
| cystic urogenital anomalies in ferrets (mustela putorius furo). | single or multiple semispherical to bilobulated fluid-filled cystic structures of variable size were observed on the dorsal aspects of the urinary bladder of four male and two female ferrets (mustela putorius furo). all ferrets had been neutered. on physical examination, the cysts were palpated as caudal abdominal masses. three of the six ferrets presented with dysuria, and two ferrets had signs compatible with endocrine dysfunction. adrenal cortical hyperplasia or neoplasia were observed in all ... | 1996 | 8801708 |
| sequence comparisons of a/aa/6/60 influenza viruses: mutations which may contribute to attenuation. | influenza virus infection is a worldwide public health threat. cold-adaptation was used to develop a vaccine line (ca a/aa/6/60 h2n2) which promised to reduce the morbidity and mortality associated with influenza and to serve as a model for other live virus vaccines. this study establishes that two distinct lines of wt a/aa/6/60 viruses exist with different phenotypic and genotypic characteristics. the two virus lines have the same parent but different passage histories. the first line is both t ... | 1996 | 8806171 |
| neurogenesis and cell migration into the sexually dimorphic preoptic area/anterior hypothalamus of the fetal ferret. | a sexually dimorphic male nucleus (mn) of the preoptic area/anterior hypothalamus (poa/ah), comprising large, estradiol-receptor containing neurons, is formed in male ferrets due to the action of estradiol, derived from the neural aromatization of circulating testosterone, during the last quarter of a 41-day gestation. two experiments were conducted to compare the birthdates and the migration pattern of cells into the sexually dimorphic portion of the dorsomedial poa/ah as well as the nondimorph ... | 1996 | 8807525 |
| spontaneous development of fatty liver in ferrets in a toxicology study. | ferrets were maintained for 12 months on different diets (a, meat and biscuit; b, all meat; c, meat and fish; d, high fibre) to ascertain the cause of spontaneous development of fatty liver. high hepatic triglyceride contents resulted on diets b = c > d; whereas ferrets on diet a (control) showed no accumulation of lipid in liver. serum triglyceride and total cholesterol were unchanged by diet. these ferrets (f0 generation) were mated with ferrets on the same diet and the offspring (f1 generatio ... | 1996 | 8814340 |
| are the interlaminar zones of the ferret dorsal lateral geniculate nucleus actually part of the perigeniculate nucleus? | the ferret dorsal lateral geniculate nucleus (lgnd) contains interneurons within the interlaminar zones situated between the laminae corresponding to the ipsi- and contralateral eyes. we found that a subset of these neurons exhibits electrophysiological properties similar to those previously reported for perigeniculate (pgn) neurons, including the generation of rhythmic sequences of rebound low-threshold ca2+ spikes at a frequency of 1-4 hz after the intracellular injection of a hyperpolarizing ... | 1996 | 8815875 |
| development of orientation preference maps in ferret primary visual cortex. | the development of orientation preference maps was studied in ferret primary visual cortex using chronic optical imaging of intrinsic signals. the emergence and maturation of the maps were examined over time in single animals. the earliest age at which cortical domains selectively responsive to particular stimulus orientations were observed varied considerably between individuals, from postnatal day 31 to 36. in all cases, the earliest maps seen were low-contrast, with regions of orientation-spe ... | 1996 | 8815923 |
| inhibition of the inferior olive during conditioned responses in the decerebrate ferret. | output from the interpositus nucleus can inhibit the inferior olive, probably via the gaba-ergic nucleo-olivary pathway. it has been suggested that the function of this inhibition might be to regulate synaptic plasticity resulting from parallel fibre/climbing fibre interaction in cerebellar purkinje cells, by providing negative feedback information to the olive. thus, when a learned response, generated by the interpositus nucleus, reaches a sufficient amplitude, the olive would be inhibited and ... | 1996 | 8817254 |
| biliary coccidiosis in a ferret (mustela putorius furo). | this report documents the first case of biliary coccidiosis in the ferret. multiple life stages of a coccidian parasite, including meronts, gametocytes, and oocysts were present in the epithelium of hepatic bile ducts and the gallbladder. based on morphologic characteristics, the organisms were identified as eimeria sp., most likely e. furonis. | 1996 | 8817844 |
| vaccination of black-footed ferret (mustela nigripes) x siberian polecat (m. eversmanni) hybrids and domestic ferrets (m. putorius furo)against canine distemper. | an inactivated canine distemper vaccine with adjuvant and a modified-live virus (mlv) vaccine were evaluated using black-footed ferret (mustegla nigripes) x siberian polecat (mustela eversmanni) hybrids us surrogates for endangered black-footed ferrets. for comparative purposes, we also vaccinated domestic ferrets (mustela putorius furo) with the mlv vaccine. response to vaccination was measured by clinical observation, hematology, dynamics of serum virus neutralizing antibodies, and challenge w ... | 1996 | 8827666 |
| digestive lipases of the newborn ferret: compensatory role of milk bile salt-dependent lipase. | the amount of mrna hybridizing to bile salt-dependent lipase and to colipase-dependent lipase probes as well as their translation into active proteins were quantified in the adult and newborn pancreas and lactating mammary gland from the ferret, a species whose milk, similar to that of the human, has bile salt-dependent lipase. the concentration of colipase-dependent lipase mrna correlated with the amount of activity found in the adult and newborn pancreas, whereas neither mrna nor activity of t ... | 1996 | 8827775 |
| demodicosis in ferrets (mustela putorius furo). | this report describes the clinical signs, diagnosis, and therapy of demodicosis in ferrets. two ferrets (mustela putorius furo) were presented with a history of local alopecia and pruritus after repeated treatment with a glucocorticoid-containing ointment for recurrent ear mite infections. skin scrapings and biopsies revealed adult mites and larvae of demodex spp., which were measured according to current classification techniques. treatment with amitraz was effective and did not cause noticeabl ... | 1996 | 8833611 |
| a transient phase of cell death in the developing medial forebrain of the perinatal ferret. | a transient bilateral population of cells immediately rostral to the ferret corpus callosum was examined at weekly intervals between embryonic day 28 and postnatal day 7. this region is tentatively identified as the medial forebrain apoptosis zone (mfaz) because of the specific nature of cell death, and the limited area or zone in which it was observed. no other region within the brain or retina exhibited a similar pattern or amount of cell death. only scattered apoptotic cells were found throug ... | 1996 | 8836574 |
| the pharmacology of the emetic response to upper gastrointestinal tract stimulation in suncus murinus. | this paper is the first to describe aspects of the mechanics of retching in the insectivore suncus murinus (house musk shrew) and in an animal of such a small size (approximately 50 g). in anaesthetised animals using the novel stimulus of mechanical stimulation of the upper gastrointestinal tract as the provocative stimulus the frequency of retching was found to be about 4 retches/s, a much higher frequency than in other species (dog, cat, ferret). these studies show that quantification of retch ... | 1996 | 8836619 |
| ferret mothers provide more anogenital licking to male offspring: possible contribution to psychosexual differentiation. | european ferret (mustela putorius furo) mothers displayed significantly higher levels of anogenital licking (agl) towards male as opposed to female kits in tests given on postpartum (p) days 6, 12, and 15. in these tests the entire litter was removed from the nestbox for 10 min, whereupon individual male and female kits were reintroduced to the mother in a counterbalanced order. in a second study an analysis of videotapes, sampled over the 24 h of several days, showed that mothers provided signi ... | 1996 | 8840891 |
| magnesium and hydrogen ions inhibit sarcoplasmic reticulum function in cardiac muscle. | we investigated the direct effects of magnesium and hydrogen ions (mg2+ and h+) on cardiac sarcoplasmic reticulum (sr) functions using saponin-treated ferret ventricular muscles. ca2+ uptake function and the ca(2+)-induced ca2+ release (cicr) mechanism were examined. for the analysis of ca2+ uptake, the sr was loaded with ca2+ under various conditions and the ca2+ content of sr was estimated by releasing ca2+ with 50 mm caffeine. to determine cicr, following ca2+ loading of the sr, solutions wit ... | 1996 | 8841928 |
| on muscarinic control of neurogenic mucus secretion in ferret trachea. | 1. muscarinic receptor subtypes mediating neurogenic mucus secretion in ferret trachea were characterized in vitro and in vivo using 35so4 as a label for secreted mucus, and the muscarinic receptor antagonists telenzepine for the m1 receptor subtype, methoctramine for the m2 subtype and 4-diphenylacetoxy-n-methylpiperidine methobromide (4-damp) for the m3 receptor. we also performed receptor binding and mapping studies. 2. each muscarinic antagonist displaced [n-methyl-3h]scopolamine binding wit ... | 1996 | 8842014 |
| effects of cyclopiazonic acid and ryanodine on cytosolic calcium and contraction in vascular smooth muscle. | 1. in smooth muscle, both ca2+ release from the sarcoplasmic reticulum (sr) and ca2+ influx across the plasma membrane are responsible for the increase in the cytosolic ca2+ level ([ca2+]i). to understand further the role of sr on smooth muscle contraction, the effects of an inhibitor of the sr ca2+ pump, cyclopiazonic acid (cpa 10 microm), an inhibitor of the ca(2+) -induced ca2+ release, ryanodine, (10 microm), and an activator of the ca(2+) -induced ca2+ release, caffeine (20 mm), on [ca2+]i ... | 1996 | 8842436 |
| neurochemical characterization of intrinsic neurons in ferret tracheal plexus. | although neuroanatomical and neurophysiological features of neurons in the ferret trachea have been studied, the neural mediators associated with this plexus have not been completely characterized. the purpose of this study was to examine the occurrence of choline acetyltransferase (chat), nitric oxide synthase (nos), vasoactive intestinal peptide (vip), and substance p(sp) in the intrinsic neurons of this plexus. the distribution of double- and triple-labeled neurons was quantified in cryostat ... | 1996 | 8845170 |
| the anti-emetic activity of gk-128 in suncus murinus. | in suncus murinus, various emetic responses and the anti-emetic activity of a new 5-hydroxytryptamine3 (5-ht3) receptor antagonist, gk-128 (2-[(2-methylimidazol-1-yl) methyl benzo[f]thiochromen-1-one monohydrochloride hemihydrate), were investigated. cancer chemotherapeutic agents, cisplatin and cyclophosphamide, dose-dependently induced emesis of long-lasting duration. the 5-ht3 receptor agonist, 2-methyl-5-ht, and copper sulfate also induced emesis of short duration. however, another 5-ht3 rec ... | 1995 | 8846809 |
| comparison of ultra-slow, voltage-dependent inactivation of the cardiac l-type ca2+ channel with ca2+ or ba2+ as the charge carrier in ferret ventricular myocytes. | the whole-cell patch clamp technique was used to investigate the effect of different charge carriers upon ultra-slow voltage-dependent inactivation of l-type ca2+ channel current in ferret ventricular myocytes at 37 degrees c. intracellular ca2+ was buffered with 10 mm egta and the membrane potential held at -40 mv. with ba2+ as the charge carrier, the l-type current decayed throughout 20 s pulses to 0 mv as a result of ultra-slow voltage-dependent inactivation. in contrast, with ca2+ as the cha ... | 1996 | 8853266 |
| a preliminary study of sleep in the ferret, mustela putorius furo: a carnivore with an extremely high proportion of rem sleep. | sleep and wakefulness were studied polygraphically in two adult male ferrets between the ages of 3 months and 2.5 years. nine 24-hour recordings were obtained on different light/dark schedules, and one animal was also monitored for 3 days following administration of the serotonin synthesis inhibitor, parachlorophenylalanine. stage scoring was accomplished utilizing criteria similar to those used in the cat. certain modifications to the criteria were made to accommodate apparent differences in el ... | 1996 | 8855029 |
| novel 5-hydroxytryptamine (5-ht3) receptor antagonists. iii. pharmacological evaluations and molecular modeling studies of optically active 4,5,6,7-tetrahydro-1h-benzimidazole derivatives. | the r- and s-enantiomers of the 4,5,6,7-tetrahydro-1h-benzimidazole derivatives 3-8 were prepared by optical resolution. each r-isomer, except for 3, was almost two orders of magnitude more potent than its s-isomer as a 5-hydroxytrptamine (5-ht3) receptor antagonist, as judged from they effect on the von bezold-jarisch reflex (b. j. reflex) in rats, the contraction of isolated guinea-pig colon and the receptor-binding affinity. the (--)-(r)-5-[(1-methyl-1h-indol-3-yl)carbonyl] derivative 6r.hcl ... | 1996 | 8855365 |
| effects of levosimendan on myocardial contractility and oxygen consumption. | levosimendan is hypothesized to be primarily a calcium sensitizer in vitro. therefore, its inotropic action may be similar in both the normal and the congestive heart failure (chf) state, and it may be associated with a decreased energetic cost of inotropism in vivo. to test these hypotheses, we gave levosimendan to cross-circulated isolated hearts from normal (n = 11) and chf (n = 7, 4-week rapid pacing) dogs. peak isovolumic left ventricular pressure at an end-diastolic pressure of 5 mm hg (pm ... | 1996 | 8858984 |
| mechanisms of the inotropic effects of ud-cg 212 cl, an active metabolite of pimobendan, on ferret papillary muscles. | we investigated the effects of an active metabolite of pimobendan, ud-cg 212 cl, on ca(2+) transients and tension using the aequorin method. when extracellular [ca(2+)] ([ca2+]o) in the tyrode's solution was 2 mm, ud-cg 212 c1 (10(-7)-10(-4)m) increased the peak of ca(2+) transients, accompanying a slight increase in peak tension. when [ca(2+)]o was decreased to 0.5 mm, the twitch-potentiating effect of ud-cg 212 c1 was more remarkable, but the increase in the ca(2+) transients at low concentrat ... | 1996 | 8859937 |
| movement of the epiglottis in mammals. | in contrast to adult humans, the epiglottis of other mammals and infant humans is situated close to the soft palate. it has been argued that this posture is maintained during swallowing, with food passing laterally around an intact airway. to test this supposition, the movement of the epiglottis in two contrasting mammalian species, pigs and ferrets, was studied by placing radiopaque markers on the epiglottis and soft palate. swallowing was observed with videofluoroscopy while the animals were f ... | 1996 | 8859955 |