Publications

distemper vaccination in ferrets.		1990	2301133
mechanism of ischemic contracture in ferret hearts: relative roles of [ca2+]i elevation and atp depletion.	when coronary perfusion is interrupted, the diastolic force generated by the myocardium first falls but eventually increases. the delayed rise in force, ischemic contracture, has been attributed either to atp depletion or to elevation of the intracellular free calcium concentration ([ca2+]i). to distinguish between these possibilities, we measured [ca2+]i and atp concentration [( atp]) in ferret hearts using nuclear magnetic resonance (nmr) spectroscopy. mean time-average [ca2+]i and [atp] equal ...	1990	2301617
the influence of ph on ca2+ exchange in ferret heart mitochondria.	the effect of ph changes on ca2+ transport by isolated heart mitochondria was measured. two components of ca2+ transport were identified, an accumulation dependent on mitochondrial respiration and a na+-dependent efflux. a decrease of ph over the range 7.7-6.7 reduced the initial rate and the total amount of respiration dependent ca2+ accumulation. at ph 7.2 the [na+] required to activate half-maximal efflux, k1/2, was 7.5 +/- 1.1 mm. decreasing the ph over the range 7.7 to 6.9 increased the k1/ ...	1990	2306247
changes in intracellular calcium during mechanical alternans in isolated ferret ventricular muscle.	alternans in heart is important as pulsus alternans in cardiac failure and electrophysiological alternans in myocardial ischemia. the explanation of this phenomenon is still unclear. we attempted to investigate the cellular mechanisms of alternans by measuring intracellular free calcium concentration [( ca2+]i) with the photoprotein aequorin in isolated ferret papillary muscles. tension and length were also recorded simultaneously. transient mechanical alternans lasting five to 20 contractions c ...	1990	2306800
measurement of dietary and dentifrice effects upon calculus accumulation rates in the domestic ferret.	most animal models for the study of calculus accumulation and control currently use rodents or dogs. in an effort to overcome limitations inherent in the use of these species, we investigated calculus formation in domestic ferrets, a species used by king et al. in the 1940's and 1950's. ferrets are much smaller than dogs, and, unlike rodents, can be scored while alive. in this study, we examined the kinetics of calculus formation in female ferrets fed with moist canned cat food--either plain or ...	1990	2307747
cocirculation of two distinct evolutionary lineages of influenza type b virus since 1983.	during 1988-1989 two highly distinct antigenic variants of influenza type b were recognized in hemagglutination-inhibition tests with postinfection ferret serum. these viruses were antigenically related to either b/victoria/2/87, the most recent reference strain, or b/yamagata/16/88, a variant that was isolated in japan in may 1988. all influenza b viruses isolated in the united states during an epidemic in the winter of 1988-1989 were antigenically related to b/victoria/2/87. however, in severa ...	1990	2309452
nerve stimulation releases mucosa-derived inhibitory factors, both prostanoids and nonprostanoids, in isolated ferret trachea.	the influence of an intact mucosa layer in isolated ferret trachea on the contractile responses to repeated, short-lasting (20 s, every 2 min) nerve stimulations was studied in a nerve-muscle preparation stimulated to cholinergic-evoked contractions by either direct vagal nerve stimulation (dns) or transmural electrical field stimulation (efs). the contractile responses were monitored by three strain gauges connected to the proximal, middle, and distal segments of the trachea. the mucosa was eit ...	1990	2310103
gastric nitrite processing in the surgically altered maximal and minimal bile reflux ferret model.	ingested nitrate and nitrite have been shown to contribute to endogenous, n-nitroso compound formation in man and experimental animals. n-nitroso compounds have long been suspected of contributing to higher levels of gastric cancer in various populations. reconstructive gastric surgery to treat ulcers is accompanied by a change in bile reflux, gastritis and an increased incidence of gastric cancer in humans. to evaluate possible connections between gastric nitrite processing, reconstructive surg ...	1990	2311183
does leukotriene c4 mediate hypoxic vasoconstriction in isolated ferret lungs?	to evaluate leukotriene (lt) c4 as a mediator of hypoxic pulmonary vasoconstriction, we examined the effects of fpl55712, a putative lt antagonist, and indomethacin, a cyclooxygenase inhibitor, on vasopressor responses to ltc4 and hypoxia (inspired o2 tension = 25 torr) in isolated ferret lungs perfused with a constant flow (50 ml.kg-1.min-1). pulmonary arterial injections of ltc4 caused dose-related increases in pulmonary arterial pressure during perfusion with physiological salt solution conta ...	1990	2312466
oestrus control in the ferret.		1990	2316138
laboratory properties of cold-adapted influenza b live vaccine strains developed in the us and ussr, and their b/ann arbor/1/86 cold-adapted reassortant vaccine candidates.	the adaptation of two influenza b strains (b/leningrad/14/55 and b/ann arbor/1/66) to replication at 25 degrees c is described. comparison of the two viruses indicates that both also exhibit temperature sensitive phenotypes, although that of the virus b/leningrad/14/55 is less pronounced. when inoculated into ferrets both viruses replicate well in the trachea, but only the b/leningrad/14/55 cold-adapted virus replicates in the lungs. this virus exhibited a moderate level of attenuation in the an ...	1990	2316285
investigation of ecdysteroid excretion by adult dirofilaria immitis and brugia pahangi.	the excretion of ecdysteroids by the filarial nematode species, dirofilaria immitis and brugia pahangi, was examined both in vitro, by the analysis of culture medium, and in vivo, through analysis of serum samples from experimentally infected hosts. there was no evidence of ecdysteroid excretion by intact parasites of either species in vitro. free ecdysteroids were detected in the serum of ferrets and dogs infected with d. immitis, but concentrations would be at or below the limit of detection i ...	1990	2320053
injection of microfilariae induces resistance to brugia malayi infection in ferrets and accelerates development of lymphostatic disease.	ferrets injected intravenously with living microfilariae or cutaneously with microfilariae followed by intravenous injection developed partial resistance to a challenge infection as measured by recovery of adult filariae from lymphatics. following a challenge infection, the ferrets injected with microfilariae developed lymphatic pathology characteristic of a chronic infection or that observed following multiple infections. there was disruption of lymphatic drainage of the infected limb and lymph ...	1990	2320382
the nuclear-cytoplasmic [ca2+] gradient in single mammalian vascular smooth muscle cells.	we studied the nuclear-cytoplasmic [ca2+] gradient in single, freshly dispersed smooth muscle cells from the ferret portal vein, by means of fluorescence ratio imaging microscopy. cells were loaded with the cell-permeant calcium indicator fura-2 am. caffeine and platelet-derived growth factor (pdgf) were used in order to mobilize ca2+ from the sarcoplasmic reticulum. basal levels of nuclear and cytoplasmic [ca2+] were 299 +/- 51 nm and 141 +/- 23 nm respectively (n = 10, p less than 0.001). at 3 ...	1990	2320603
vaccines authorized for use in ferrets.		1990	2321346
use of the ferret for a myocardial ischemia/salvage model.	exploratory work was undertaken in the anesthetized ferret to determine if it is an applicable species for use as an in vivo ischemic model and suitable for recovery surgical procedures. experimental protocols utilizing varying combinations of left anterior descending (lad) coronary artery occlusion (30, 60, 90 min) and reperfusion (4, 6, 18-24 hr) were evaluated. the results indicated that a 90-min/6-hr combination led to the production of an infarct equivalent, or slightly greater, in size to ...	1990	2329802
auditory brainstem of the ferret: maturation of the brainstem auditory evoked response.	a longitudinal study of developmental changes in the brainstem auditory evoked response (baer) was made on 19 ferrets between postnatal days 25 (p25) and 50. responses to free-field click stimuli were recorded from anaesthetized animals, and compared with data obtained from 8 adult ferrets. a reproducible baer was first recordable on p27, although the response onset was generally later in smaller animals. baer onset preceded eye opening, which started on p32. adult-like thresholds were observed ...	1990	2331796
mechanism of myocardial contractile depression by clinical concentrations of ethanol. a study in ferret papillary muscles.	moderate alcohol intoxication in man, a ubiqitious social event, causes acute but reversible myocardial depression, the mechanism of which is unknown. we investigated whether this depression could be due to a direct effect of ethanol on the process of electromechanical coupling by simultaneously measuring the transmembrane action potential and contraction, or the cytosolic calcium transient (via aequorin photoluminescence) and contraction in isolated ferret right ventricular papillary muscle. et ...	1990	2332501
nitrate biosynthesis in rats, ferrets and humans. precursor studies with l-arginine.	l-arginine, the primary nitrogen source for nitric oxide synthesized by many cell types in culture and for biosynthesized nitrate in humans, is also a nitrogen source for biosynthesized nitrate in rats and ferrets. after administration of [15n2]l-arginine to rats and ferrets, [15n]no3- was detected in urine. escherichia coli lipopolysaccharide induced more than a 10-fold increase in urinary nitrate in rats and a parallel increase in incorporation of 15n from [15n2]l-arginine into no3-. bradykini ...	1990	2335012
excitation-contraction coupling in postischemic myocardium. does failure of activator ca2+ transients underlie stunning?	to elucidate the mechanism of contractile dysfunction in postischemic ("stunned") myocardium, time-resolved measurements of intracellular free ca2+ concentration ([ca2+]i) were made using gated 19f nuclear magnetic resonance in seven perfused ferret hearts loaded with the fluorinated ca2+ indicator 5f-bapta. left ventricular developed pressure decreased to 65 +/- 3% (mean +/- sem) of control after 15 minutes of global ischemia at 37 degrees c. in stunned myocardium, diastolic [ca2+]i (0.24 +/- 0 ...	1990	2335025
clinical interpretation: the hermeneutics of medicine.	i argue that clinical medicine can best be understood not as a purified science but as a hermeneutical enterprise: that is, as involved with the interpretation of texts. the literary critic reading a novel, the judge asked to apply a law, must arrive at a coherent reading of their respective texts. similarly, the physician interprets the 'text' of the ill person: clinical signs and symptoms are read to ferret out their meaning, the underlying disease. however, i suggest that the hermeneutics of ...	1990	2339336
optokinetic nystagmus in the ferret: including selected comparisons with the cat.	the aim of this study was to evaluate the functional significance of similarities observed in the anatomy and the physiology of cat and ferret visual systems. optokinetic nystagmus (okn) in response to movement of the entire visual field, and optokinetic after nystagmus (okan) were measured in 8 ferrets with binocular stimulation. a shift of the beating field in the same direction as the fast phase of eye movements was observed both in ferret and cat. the absence of a fast rise in slow phase vel ...	1990	2340879
a domestic ferret model of immunity to campylobacter jejuni-induced enteric disease.	oral or intravenous inoculation of previously unexposed juvenile and adult ferrets with campylobacter jejuni uniformly resulted in intestinal colonization lasting 2 to 12 days. disease varied from mild to moderate diarrhea, which resolved in 2 to 3 days. orally infected animals developed agglutinin titers of 8 to 256 within 3 weeks, while those infected intravenously developed titers of 256 to 2,048. ferrets which had recovered from campylobacteriosis all developed high titers of agglutinating a ...	1990	2341180
dendritic morphology and development in the ferret medial superior olivary nucleus.	dendritic morphology and development in the medial superior olivary nucleus of the ferret were studied using the golgi method. in the adult ferret most medial superior olivary neurons had disk-shaped dendritic fields. these dendritic fields were oriented such that cells in a coronal plane of section appeared bipolar with major lateral and medial dendritic axes. in the horizontal plane the dendrites radiated about the soma. dendrites of principal cells branched distally into tufts of numerous, te ...	1990	2341617
synaptic organization in the adult ferret medial superior olive.	the ultrastructure of the medial superior olive (mso) was studied in the adult ferret. the synaptic terminals were categorized on the basis of morphology and their distribution determined. there are three types of synaptic terminals: r terminals, containing round vesicles; ov terminals, containing ovoid vesicles; and p terminals, containing vesicles of varying morphologies. r terminals are the dominant terminal type on both the somata and dendrites. ov and p terminals are equally prevalent on th ...	1990	2341618
cardiotonic agents. 6. histamine analogues as potential cardiovascular selective h2 agonists.	twenty-six alkyl and aralkyl histamine analogues were prepared as potential cardiotonic agents. compounds were designed to allow interaction with a putative secondary aryl binding site at the h2 receptor, the presence of which was inferred from the structure of cyprohepatadine, which is known to have h2-antagonist properties. the compounds were examined for inotropic activity in ferret papillary muscle. potent inotropic activity was generally found in n-alkyl- and n,n-dialkylimidazole-4-ethanami ...	1990	2342063
evaluation of an inactivated rabies virus vaccine in domestic ferrets.	efficacy of an sc-administered commercial inactivated vaccine for prevention of rabies was evaluated in domestic ferrets. ferret immunity was challenged by the im inoculation of street rabies virus. all ferrets developed titers of rabies virus-neutralizing antibodies within 30 days of vaccination (geometric mean titer [gmt] = 154, n = 41) that were maintained for at least one year (gmt = 106, n = 36), compared with no seroconversion in controls (gmt less than 5, n = 39). following rabies virus c ...	1990	2347753
the effects of 2,3-butanedione monoxime on initial heat, tension, and aequorin light output of ferret papillary muscles.	at low concentrations (up to 5 mm) the compound 2,3-butanedione monoxime (bdm) was found to reduce twitch tension and initial heat production in isolated papillary muscles without significantly affecting the size of the intracellular ca2+ transient measured with aequorin luminescence. higher concentrations of bdm caused further inhibition of twitch tension and heat production with a fall in the size of the ca2+ transient. the size of the aequorin transient was 50% of the control value at 15 mm b ...	1990	2352836
effects of zacopride and bmy25801 (batanopride) on radiation-induced emesis and locomotor behavior in the ferret.	the antiemetic and locomotor effects of two substituted benzamides, zacopride and batanopride (bmy25801), were compared in ferrets after bilateral 60co irradiation at 2, 4 or 6 gy. both zacopride and bmy25801 were effective against emesis and related signs. zacopride, tested at several doses (0.003, 0.03 and 0.3 mg/kg), appeared to be more potent because it abolished emesis at 100-fold lower doses than did bmy25801 (3 mg/kg). the ed50 value for the antiemetic effect of zacopride was 0.026 mg/kg ...	1990	2359014
effects of corticosteroids on postnatal lung and airway growth in the ferret.	to investigate the influence of corticosteroids on postnatal lung and airway growth, young male ferrets were given cortisone acetate (20 mg/kg im daily) beginning at 8 wk of age. at 19 wk of age pulmonary function was measured. the lungs were excised for measurements of recoil pressures and wet and dry weights. the dimensions of central and peripheral airways were estimated from analysis of bronchial casts. corticosteroid-treated animals were shorter and tended to be lighter than control animals ...	1990	2361904
5-hydroxytryptamine (5-ht3) receptor antagonists. 1. indazole and indolizine-3-carboxylic acid derivatives.	metoclopramide (1) is a gastric motility stimulant and a weak dopamine and 5-ht3 receptor antagonist. conformational restriction of the (diethylamino)ethyl side chain of 1 in the form of the azabicyclic tropane gave 3, a very potent gastric motility stimulant and 5-ht3 receptor antagonist but devoid of significant dopamine receptor antagonist properties. subsequent alteration of the aromatic nucleus led to the identification of indazoles 6a-h, and 1- and 3-indolizines 7b-d and 8, and imidazo[1,5 ...	1990	2362270
helicobacter mustelae-associated gastritis in ferrets. an animal model of helicobacter pylori gastritis in humans.	gastric helicobacter mustelae was present in 100% of 11 adult female ferrets (mustela putorius furo). the high immunoglobulin g antibody levels to h. mustelae in all ferrets showed a significant immune response to the organism. urease mapping of the ferret stomach indicated that the bacteria heavily colonized the proximal duodenum and antrum and, to a lesser extent, the corpus. the histological gastritis observed coincided with presence of h. mustelae. superficial gastritis was noted in the oxyn ...	1990	2365188
endocrine correlates of mating-induced reductions in estrous behaviour in an induced ovulator, the ferret.	experiments were conducted to assess the time course of behavioral and endocrine changes which occur in female ferrets as they switch from estrus to the pseudopregnant state. significant reductions in females' acceptance of neck gripping by a stimulus male (receptivity) and in their latency to approach a stimulus male in an l-maze (proceptivity) were first observed 3 days after receipt of an intromission; no such changes occurred in other females which were only neck gripped by stimulus males du ...	1990	2365301
aleutian disease in the ferret.		1990	2368310
kinins are generated in nasal secretions during influenza a infections in ferrets.	infection of ferrets with influenza a virus results in a disease syndrome that is similar to that observed in humans. to examine the pathophysiology of this disease, ferrets were challenged with either h1n1 influenza virus or placebo. sign scores and rectal temperatures were recorded periodically during the 9 days after infection. nasal lavages were also collected during this time period and the content of kinins, histamine, cells, and total protein in these lavages was assessed. in infected ani ...	1990	2368965
lack of detectable blood groups in domestic ferrets: implications for transfusion.	evidence of blood groups in domestic ferrets was sought by testing serum samples for naturally acquired or experimentally induced erythrocyte antibodies. all sera were tested for ability to cause direct agglutination, antiglobulin-enhanced (coombs test) agglutination, or lysis. examination of 212 randomly paired combinations of ferret serum and erythrocytes produced no evidence of naturally acquired blood group antibodies. six pairs of ferrets were reciprocally transfused twice, 34 days apart, w ...	1990	2370225
drug effects on function in the ferret ischemic hindlimb.	in this article a new model of peripheral occlusive arterial disease is described. the lower hindlimb of an anesthetized ferret was fixed to a holder, the distal end of the achilles tendon attached to an isometric force transducer, and a passive preload of 100 g was applied to the muscle preparation. the hindlimb was stimulated to contract isometrically via supramaximal electrical stimulation of the sciatic nerve. during the initial period, when femoral blood pressure equaled aortic blood pressu ...	1990	2370804
helicobacter pylori-like microorganisms and chronic active gastritis in ferrets.	to determine the prevalence and histology of helicobacter pylori (hp) associated gastritis in young ferrets, we examined 36 normal 2- to 4-month old ferrets. identification of hp-like microorganisms included warthin starry stains of tissue sections, rapid urease test on fresh tissue, and culture. hp-like microorganisms were found in the stomachs of 35/36 ferrets. the highest density of microorganisms was seen in the antrum, where hp-like microorganisms were present in the pits and in deep glands ...	1990	2371981
relative roles of ca2(+)-dependent and ca2(+)-independent mechanisms in hypoxic contractile dysfunction.	contractile function is known to be impaired during hypoxia or metabolic inhibition, but the relative importance of activator ca2+ deficiency compared with the accumulation of depressant metabolites remains controversial. to distinguish between these possibilities, we used nuclear magnetic resonance (nmr) spectroscopy to measure the most likely mediators--intracellular [ca2+] [( ca2+]i), inorganic phosphate concentration [( pi]), and ph--before and during hypoxia in perfused ferret hearts. ca2+ ...	1990	2372899
functional organization in the ferret visual cortex: a double-label 2-deoxyglucose study.	the functional organization of visual cortical area 17/18 of the ferret was studied using a double-label 2-deoxyglucose (2-dg) method. animals were stimulated sequentially with moving gratings of 2 different orientations. elongated orientational patches running roughly at a right angle into the area 17/18 border were seen. the orientation maps were similar in areas 17 and 18. when animals were stimulated with 2 orthogonally oriented gratings, activation patterns were not fully complementary but ...	1990	2388088
mechanical restitution in isolated mammalian myocardium: species differences and underlying mechanisms.	ventricular myocardium was obtained from guinea-pig, ferret and human hearts. in each case small strips were mounted isometrically in a tissue bath and superfused with a physiological saline at 37 degrees c. the preparations were stimulated at 1 hz and ectopic stimuli of different preceding intervals were given. the relationship between the force produced by the ectopic contraction and the duration of the preceding interval was plotted to form mechanical restitution curves (mrc). in the guinea-p ...	1990	2388277
the effects of bathing sodium ions upon the intracellular sodium activity in calcium-free media and the calcium paradox of isolated ferret ventricular muscle.	exposure of fine trabeculae isolated from the ferret right ventricle to media depleted of ca2+, with a rapid perfusion system, causes a depolarization of the membrane and a rise in aina. this rise in aina is sigmoidally dependent upon the bathing free [ca2+], is antagonized by reduction of the [na]o, raised [mg]o and pn200-110 but augmented by removal of mg2+ or inhibition of the na-pump. on repletion of ca2+, the strength of the resulting contracture depends upon the transmembrane. na-gradient ...	1990	2388280
eradication of helicobacter mustelae from the ferret stomach: an animal model of helicobacter (campylobacter) pylori chemotherapy.	colonization of the ferret stomach by helicobacter mustelae has been suggested as a possible animal model for helicobacter pylori-associated gastroduodenal disease of humans. our study was designed to determine whether antimicrobial chemotherapy could eradicate h. mustelae from ferrets. triple antimicrobial therapy combining amoxicillin, metronidazole, and bismuth subsalicylate was successful in eradicating the organism from 5 of 7 (71%) adult ferrets. despite apparent in vitro susceptibility, n ...	1990	2393285
negative inotropy of halogenated anesthetics in ferret ventricular myocardium.	the effects of the volatile anesthetics halothane, enflurane, and isoflurane on amplitude and time variables of contraction and relaxation in isometric, isotonic, and zero-load clamped twitches of isolated right ventricular ferret papillary muscles (n = 24) were compared with those of changing extracellular ca2+ concentration [( ca2+]o). contraction and relaxation variables were compared at equal contraction amplitudes to determine whether the studied anesthetics exert specific effects on contra ...	1990	2396690
preliminary studies on the in vivo morphogenetic properties of dentine matrix proteins.	two fractions of isolated noncollagenous extracellular matrix proteins from dentine have been implanted into the base of exposed cavities in ferret canine teeth. after sealing the cavities, reparative dentinogenesis was assessed histologically after 14 and 28 days as compared to control cavities. reparative dentinogenesis was enhanced in the presence of these matrix proteins with evidence of tubular dentine along the walls of the exposure and on the cavity floor demonstrating the in vivo morphog ...	1990	2397254
topographical distribution of 5-ht3 receptor recognition sites in the ferret brain stem.	the distribution of [3h]zacopride (1.0 nm) to putative 5-ht3 receptor recognition sites in the ferret hindbrain was assessed using autoradiography. specific binding (defined by the inclusion of granisetron, 1.0 microm) was heterogeneously distributed with highest density within the dorsal vagal complex (area postrema, nucleus tractus solitarius and dorsal motor nucleus of the vagus nerve). lower densities were detected in the spinal trigeminal nerve complex whilst no other significant specific b ...	1990	2402300
immunohistochemical and morphologic features of chordomas in ferrets (mustela putorius furo).		1990	2402855
microbiological aspects of helicobacter pylori (campylobacter pylori).	the human gastric pathogen campylobacter pylori has recently been reclassified as helicobacter pylori, and a related spiral bacterium found in the stomach of ferrets has been designated helicobacter mustelae. the general microbiological features of helicobacter pylori are delineated here, with details of phenotypic differences between helicobacter pylori and helicobacter mustelae; comparisons are made with wolinella succinogenes and campylobacter jejuni. the helicobacter organisms possess an ext ...	1990	2406141
prostaglandins alter methacholine-induced secretion in ferret in vitro trachea.	the ferret trachea was mounted in an organ bath containing krebs-henseleit solution with additional bovine serum albumin (bsa). tracheal secretions were collected and analyzed for albumin, and lysozyme, a specific marker of serous cell secretion. the total secretion volume and output and concentrations of albumin and lysozyme were calculated. secretion was stimulated with methacholine (20 microm) (mch), and the effects of the prostaglandins pgd2, pge1, and pgf2 alpha on methacholine-induced secr ...	1990	2407140
steroidal control of behavioural, neuroendocrine and brain sexual differentiation: studies in a carnivore, the ferret.		1990	19215366
effect of naloxone on the pulsatile secretion of luteinizing hormone in gonadectomized male and female ferrets before and after oestradiol replacement.	abstract intravenous infusions of the opioid receptor antagonist, naloxone, caused a significant rise in luteinizing hormone (lh) pulse frequency in male and female ferrets which had been gonadectomized 10 days earlier while in breeding condition; mean lh concentrations and lh pulse amplitudes were not affected. by contrast, naloxone failed to stimulate lh pulse frequency, or other lh parameters in gonadectomized ferrets of either sex which received daily injections of a low dose of oestradiol. ...	1990	19215408
conservation biology and the black-footed ferret. ulysses s. seal, e. tom thorne, michael a. bogan, and stanley h. anderson, eds. yale university press, new haven, ct, 1989. xviii, 302 pp., illus. $40.		1990	17843324
the course of fibre diameter classes through the chiasmatic region in the ferret.	the present study has examined the transition of fibre order from the optic nerve through the optic chiasm and into the optic tract in the ferret's retinofugal pathway. semi-thin sections through the chiasmatic region were examined in normal and in monocularly enucleated ferrets in order to display the segregation of the different axon diameter classes as the fibres pass from the optic nerve into the optic tract, and to determine, for each diameter class, where the crossed and uncrossed componen ...	1990	12106101
relation between putative transmitter phenotypes and connectivity of subplate neurons during cerebral cortical development.	during development, the earliest generated neurons of the mammalian telencephalon reside in a region of the white matter, the subplate, just beneath the cortical plate. neurons in the subplate are only transiently present in the telencephalon: shortly after birth in the cat the majority have disappeared. during their brief life, however, subplate neurons mature; they extend long-distance and local projections, and express immunoreactivity for gaba and several neuropeptides. in the present study ...	1990	12106275
the distribution and morphology of corticogeniculate axons in ferrets.	this study examined the distribution of axons in the lateral geniculate (lgn) and adjacent nuclei following injections of wheat germ agglutinin bound to horseradish peroxidase (wga-hrp), [3h]proline and biocytin into area 17 in ferrets. terminal label was found in the lgn, perigeniculate (pgn), medial interlaminar (min) and lateral posterior (lp) nuclei. lgn label was more concentrated in the interlaminar zones. analysis of axonal morphology showed that different axon types project to lgn, min a ...	1990	2271942
[serorrhaphy prevents regeneration of vagus nerve fibers after proximal gastric vagotomy].	spouting or regeneration of vagus fibers occurs after vagotomy. an axonal tracing method was used to see the long-term effect of serorrhaphy in the prevention of axonal regeneration after proximal gastric vagotomy (pgv) in ferrets.	1990	2233669
response of pocket gophers (thomomys talpoides) to an operational application of synthetic semiochemicals of stoat (mustela erminea).	this paper reports on laboratory bioassays and a large-scale field trial of synthetic mustelid anal-gland compounds in controlled-release devices designed for operational application to burrow systems of northern pocket gophers (thomomys talpoides). the field study was conducted in an apple orchard in the okanagan valley of british columbia. in laboratory bioassays, a 1∶1 mixture of 2-propylthietane and 3-propyl-1,2-dithiolane from the stoat (mustela erminea) and 3,3-dimethyl-1,2-dithiolane from ...	1990	24263607
photomanipulation of sexual maturation and breeding cycle of the steppe polecat (mustela eversmanni) and other techniques for more rapid propagation of the species.	twenty steppe polecats were divided into 2 groups, each consisting of 4 males and 6 females, and subjected to either a natural photoperiod (controls) or alternating periods of short (8 h light/16 hr dark for 8-9 weeks) and long days (16 h light/8 h dark for 16-20 weeks). the experimental photoperiod significantly accelerated sexual maturation in both sexes, with males developing maximal testis size within 57 days and females breeding after an average of 52 days exposure to 16l/8d. males in the e ...	1990	2388043
mechanical removal of airway epithelium disrupts mast cells and releases granules.	many previous investigators have utilized mechanical rubbing as a method for examining effects of epithelial removal. in the present study, we examined whether this procedure also affects mast cell integrity in the underlying lamina propria. we isolated bronchial rings from six ferrets, and we found that removal of epithelium by rubbing decreased the total number of intact mast cells from 10.0 +/- 1.9 to 2.2 +/- 0.6 (se) mast cells/mm luminal perimeter (p less than 0.01). in addition, we found a ...	1990	2260671
a map of visual space induced in primary auditory cortex.	maps of sensory surfaces are a fundamental feature of sensory cortical areas of the brain. the relative roles of afferents and targets in forming neocortical maps in higher mammals can be examined in ferrets in which retinal inputs are directed into the auditory pathway. in these animals, the primary auditory cortex contains a systematic representation of the retina (and of visual space) rather than a representation of the cochlea (and of sound frequency). a representation of a two-dimensional s ...	1990	2237432
role of vagal afferent c fibres in the bradycardiac response to an increase in arterial blood pressure in ferrets.	the effects on baroreceptor reflexes of bilateral application of the c fibre neurotoxin, capsaicin, to the cervical vagi have been investigated in decerebrate ferrets. baroreflex sensitivity was estimated from the relationship between cardiac interval and systolic blood pressure following i.v. infusion of phenylephrine. control responses to phenylephrine were fitted by two linear slopes with an initial shallow slope, a, followed by a steeper slope, b. capsaicin abolished slope b and the resultin ...	1990	2271165
effects of dexmedetomidine on contractility, relaxation, and intracellular calcium transients of isolated ventricular myocardium.	the effects of the highly selective alpha 2-adrenoceptor agonist dexmedetomidine on contractility, relaxation, and the intracellular ca2+ transients of isolated ventricular myocardium were studied in isolated right ventricular papillary muscles obtained from reserpinized ferrets. dexmedetomidine (10(-10)-10(-5) m) did not alter amplitude and time variables of isometric, isotonic and zero-load-clamped twitches, except for a slight increase in maximal isotonic relaxation rate at 10(-5) m. dexmedet ...	1990	1978616
exposure to triphenyl phosphite results in widespread degeneration in the mammalian central nervous system.	previous studies in mammals have found that exposure to triphenyl phosphite results in cellular and axonal degeneration in the spinal cord and medulla. however, the nature of concomitant clinical signs suggested that other areas of the central nervous system might also be affected. in this study, the brains of ferrets receiving single subcutaneous injections of triphenyl phosphite were examined 8-12 days after dosing. widespread areas of axonal, terminal, and somatic degeneration were seen in me ...	1990	2289128
toxoplasmosis in ferrets.		1990	16031595
the development of the periodontal ligament with special reference to collagen fibre ontogeny.	the development of the periodontal ligament was investigated from serial sections of the mandibles of ferrets ranging in age from 42 days to 66 days post partum. both succedaneous and non-succedaneous teeth were studied and similarities were seen in both types of tooth. no significant amounts of alveolar bone were observed being deposited beneath the erupting root apices and periodontal collagen fibres were seen attached to the walls of the sockets just prior to emergence of the crown into the o ...	1990	2254296
visual projections induced into the auditory pathway of ferrets. i. novel inputs to primary auditory cortex (ai) from the lp/pulvinar complex and the topography of the mgn-ai projection.	the organization of cortical circuitry responsible for processing sensory information is a subject of intense examination. however, it is not known whether cortical cells in different sensory cortices process information in a way that is specific to the modality of their input, or whether there are commonalities in processing circuitry across different cortices. in our laboratory, this question has been investigated at the level of the geniculocortical pathway by routing information of one senso ...	1990	1698829
emetic activity of zacopride in ferrets and its antagonism by pharmacological agents.	zacopride administered orally was more emetic in fed than in fasted ferrets. the emetic activity of zacopride (0.1 mg/kg p.o.) was inhibited (100%) by 0.1 mg/kg i.p. of zacopride and 1 mg/kg i.p. of ics 205-930. haloperidol (3.16 mg/kg i.p.) and prochlorperazine (3.16 mg/kg i.p.) were weakly effective. n-acetyl-5-hydroxytryptophyl-5-hydroxytryptophan amide, a 5-ht1p antagonist, was inactive. thus, the emetic activity of zacopride, like that of cisplatin, is blocked by 5-ht3 receptor antagonists.	1990	2384137
retinofugal fibres change conduction velocity and diameter between the optic nerve and tract in ferrets.	in earlier studies of central nervous fibre tracts, it was tacitly assumed that individual axons are relatively uniform along their length. in the retinofugal pathway in particular, axon diameter, myelin thickness and correlated conduction properties have been treated as constant throughout the optic nerve, chiasm and tract. we report here that the conduction velocities of fibres contributing to the early components of the compound action potential are significantly greater in the optic tract th ...	1990	2314474
mast cell tumors in three ferrets.	pruritic open skin lesions (5 mm diameter) on the thorax, neck, or head of 3 ferrets were diagnosed as mast cell tumors. diagnosis of the tumors was based on histologic examination of biopsy specimens. histologic diagnosis was necessary because the lesions had been treated as mycotic or bacterial ulcers and did not respond to conventional treatment. excised mast cell tumors did not recur, and malignant behavior of the tumors was not observed.	1990	2106501
[elastase-induced hyperfunction of submucous glands develops independent of elastase-induced emphysema].	we instilled 2 mg of pancreatic elastase into the lungs, and insufflated a further 2 mg into the trachea of 6 male ferrets. six control animals were given 0.9% nacl (lungs) and glucose powder (trachea). this combined treatment was administered on days 1, 8 and 15. on these days, and again on days 29 and 39, we obtained chest x-rays. on the 39th day, we removed the lungs and measured the mean linear intercept. in tracheal sections, we measured goblet cell density, glandular structure and function ...	1990	2367425
prenatal and neonatal testosterone exposure interact to affect differentiation of sexual behavior and partner preference in female ferrets.	implanting testosterone (t) subcutaneously over postnatal days 5-20 masculinized sexual behavior, reduced proceptive responsiveness, and shifted sexual preference more readily in male than in female ferrets gonadectomized on day 5. this enhanced sensitivity of males to neonatal t was best duplicated in females exposed transplacentally to t over embryonic days (e) 27-39 (41-day gestation) and injected at birth with t (2.5 micrograms sc in oil: 10% ethanol). extended exposure of male ferrets to hi ...	1990	2317276
prechiasmatic reordering of fibre diameter classes in the retinofugal pathway of ferrets.	this study examines the distribution of fibre diameter classes at various sites along the retinofugal pathway of adult ferrets. light microscopic observations were made on semi-thin sections, and regional fibre diameter spectra were constructed from diameter measurements taken from electron micrographs of thin sections of the intraorbital optic nerve (2.5 mm from the optic disc), the intracranial optic nerve (1 mm rostral to the fusion of the nerves), and the optic tract (just caudal to the opti ...	1990	12106100
antitumor activity and toxicity in animals of n-7[2-(4-nitrophenyldithio) ethyl] mitomycin c (bmy-25067).	bmy-25067, n-7[2-(4-nitrophenyldithio)-ethyl] mitomycin c was selected from a number of disulfide derivatives of the highly active compound rr150, n-7(thioethyl) mitomycin c for further study. bmy-25067 had tumor inhibitory effects equivalent to mitomycin c (mmc) against ascitic p388 and l1210 leukemias and m109 lung carcinoma in mice with i.p. treatment. however, it demonstrated superior activity against b16 melanoma with a high percentage of cures when both tumors and drug were given i.p. addi ...	1990	2380013
changes in airway length after unilateral pneumonectomy in weanling ferrets.	we have previously shown that airway cross-sectional area increases 15-20% after pneumonectomy in weanling ferrets by measuring bronchial casts. we have now reanalyzed these same casts to quantitate changes in airway length after pneumonectomy. in each cast the distance from each of 120 airways to the terminal bronchiole along its axial pathway was measured. the relationship between the logarithm of this distance and that of the fraction of the lobe subtended by an airway could be described by a ...	1990	2312458
real-time ultrasonographic determination of pregnancy and gestational age in ferrets.		1990	2153873
photoperiodic regulation of gonadal growth and pulsatile luteinizing hormone secretion in male ferrets.	testicular growth was monitored in male ferrets subjected to one of the following photoperiodic treatments begun at weaning (8 weeks of age): 8 hr light/day (short days), 18 hr light/day (long days), or short days followed by transition to long days at either 10, 12, or 14 weeks of age. mean ages to achieve adult testis width of greater than or equal to 12 mm were 27.5 +/- 1.3, 25.0 +/- 1.5, 23.6 +/- 2.9, 20.0 +/- 0.8, and 21.2 +/- 1.0 weeks in ferrets raised from weaning in long days, raised fr ...	1990	2133130
'a new cageful of ferrets!'--medicine and the 'two cultures' debate of the 1950s.		1991	1843853
triggered activity as a possible mechanism for arrhythmias in ventricular hypertrophy.	to study the cellular mechanisms of arrhythmias occurring in cardiac hypertrophy, we performed standard microelectrode studies on papillary muscles isolated from control (group n) and hypertrophied ferrets right ventricles. different stages of hypertrophy, induced by pulmonary banding, were studied: 10-22 days (group h1), 4-6 weeks (h2), and 5 1/2-6 months (h3). during the development of hypertrophy, under beta-adrenergic stimulation, triggered activity (ta) induced by delayed afterdepolarizatio ...	1991	1721166
reciprocal relationships between pulsatile androgen secretion and the expression of mating behavior in adult male ferrets.	the pulsatile secretion of androgen was similar over a 12-hr period in breeding male ferrets implanted with jugular catheters which either achieved an intromission with an estrous female or received no socio-sexual contact. this negative result contrasts with the previous demonstration (carroll, erskine, and baum, 1987, endocrinology 121, 1349-1359) of a significant, delayed rise in mean plasma androgen concentrations in breeding male ferrets 5-12 hr after mating. males used in that previous stu ...	1991	1937429
neural regulation of lysozyme secretion from tracheal submucosal glands of ferrets in vivo.	to investigate how central and peripheral nerves affect lysozyme secretion from tracheal submucosal glands in ferrets we injected substance p (20 nmol/kg in 200 microliters) intracisternally or intravenously into anesthetized artificially ventilated ferrets. we collected 3-ml samples from a perfused (3 ml/5 min) segment of trachea in situ during 15 min before and 45 min after injection of substance p. content of lysozyme, a specific marker of tracheal submucosal gland serous cell secretion in fe ...	1991	1721905
british ferrets to hungry.		1991	17749900
a golgi study of dendritic development in the dorsal lateral geniculate nucleus of normal ferrets.	the development of neurons in the dorsal lateral geniculate nucleus (dlgn) of pigmented ferrets was studied by using the golgi-hortega technique. in adult ferrets, four dlgn cell classes were defined on the basis of somatic and dendritic morphology. classes 1 and 2 were divided into stellate and oriented subtypes. class 1 and 4 cells are characterized by filiform appendages, class 2 cells by club-like appendages, and class 3 cells by stalked appendages. at birth, dlgn neurons have simple dendrit ...	1991	1716647
the effects on the dental pulp of a composite resin and two dentine bonding agents and associated bacterial microleakage.	the pulpal reaction associated with a composite resin alone and composite resin used in conjunction with two dentine bonding agents was studied. class v cavities were prepared on the labial surfaces of the canine teeth of 18 male ferrets. after acid etching of the enamel margins, the cavities were restored with either a composite resin alone or in combination with one of two dentine bonding agents, scotchbond and gluma. one cavity in each animal was filled with kalzinol as a control. the animals ...	1991	1778623
testosterone in mpoa elicits behavioral but not neuroendocrine responses in ferrets.	the amount of time male ferrets were engaged in neck gripping, mounting, and thrusting was quantified in 30-min tests with a receptive female before and after castration. bilateral cannulae containing a total of approximately 2 mg testosterone propionate (tp) in cocoa butter were then stereotaxically aimed at the medial preoptic area (mpoa). tests for sexual behavior were conducted on days 3, 7, 14, and 21 postimplantation. ferrets were histologically categorized as either 1) miss (implants not ...	1991	2049603
vaginocervical stimulation of ferrets induces release of luteinizing hormone-releasing hormone.	abstract vaginocervical stimulation of ovariectomized estradiol-primed ferrets (which are reflex ovulators) with a glass rod in the presence of a neck-gripping male induced an increase in plasma luteinizing hormone (lh) from undetectable levels (</=0.50 ng/ml) before stimulation, to 2.4 +/- 0.43 ng/ml 75 min after stimulation (stimulated females). forty-eight h after stimulation plasma lh returned to baseline levels (post-stimulated females). a significant decrease in the number of perikarya con ...	1991	19215443
guanidino compound metabolism in arginine-free diet induced hyperammonemia.	guanidino compounds, intermediates of arginine metabolism, are altered in many pathological conditions especially those involving the urea cycle. arginine and creatine play an important role in nitrogen metabolism whereas other guanidino compounds such as guanidinosuccinic acid and n-acetylarginine are toxins. our objective was to investigate the relationship between guanidino compounds and hyperammonemia. young and adult ferrets were fed a single meal of either an arginine-containing diet (acd) ...	1991	1815947
exacerbation of bacterial toxicity to infant ferrets by influenza virus: possible role in sudden infant death syndrome.	of several toxins examined, only staphylococcal alpha and gamma toxin, endotoxin, and diphtheria toxins were lethal for 5-day-old ferrets. their toxicities were enhanced in animals infected at 1 day old with influenza virus, from 3-fold with staphylococcal gamma toxin through 14-fold for staphylococcal alpha toxin, 84-fold for endotoxin, and 219-fold for diphtheria toxin. no increased viral replication occurred in any tissue; thus the effects of the toxins were exacerbated by the infection, not ...	1991	1984474
mechanism of early ischemic contractile failure. inexcitability, metabolite accumulation, or vascular collapse?	the basis of early ischemic contractile failure was investigated in perfused ferret hearts at 27 degrees c. isovolumic left ventricular developed pressure fell by more than 50% within 30 seconds of the onset of total global ischemia and reached zero by 5 minutes. monophasic action potential recordings revealed no decrease in excitability during this period. phosphorus nuclear magnetic resonance spectra obtained at 30-second resolution showed no significant changes in inorganic phosphate or phosp ...	1991	1984866
mechanical alternans during acidosis in ferret heart muscle.	acidosis leads to mechanical alternans (i.e., alternation of large and small contractions) in ferret papillary muscles. this alternation in the size of the contraction is paralleled by alternation in the size of the intracellular ca2+ transient (monitored using the photoprotein aequorin). in isolated myocytes, the large contraction is accompanied by a prolonged action potential. mechanical alternans also can be induced by acidosis in isolated myocytes during a train of voltage-clamp pulses. thus ...	1991	1984873
attachment of influenza a virus to ferret tracheal epithelium at different maturational stages.	influenza virus attaches primarily to ciliated cells in mature airways epithelium. this process is mediated by a viral envelope glycoprotein (hemagglutinin) that binds to sialic acid-containing receptors in the apical membrane of host cells. the purpose of this study was to determine the cellular distribution of these receptors as a function of tracheal epithelial maturation in the ferret, which is susceptible to influenza virus infection at all ages and undergoes postnatal ciliation. to assay f ...	1991	1986780
influenza virus enhancement of membrane leakiness induced by staphylococcal alpha toxin, diphtheria toxin and streptolysin s.	release of alpha-amino[14c]isobutyric acid from ferret mpf cells was promoted by staphylococcal alpha toxin, diphtheria toxin and streptolysin s. this release was enhanced to a significant extent if the cells had been previously infected with influenza virus strain a/puerto rico/8/34 (pr8, h1n1), although infection with virus alone did not increase the release of radiolabel as compared with that from untreated cells; inactivated virus had a similar enhancing action. the mechanism of enhancement ...	1991	1990059
the effects of halothane, enflurane, and isoflurane on the length-tension relation of the isolated ventricular papillary muscle of the ferret.	the effects of halothane, enflurane, and isoflurane on the length-tension relation were investigated in papillary muscles of the right ventricle of adult male ferrets at 30 degrees c. isometric twitch contractions were obtained at lengths ranging from the shortest length yielding the greatest active force development under isometric conditions (lmax) to 86% of lmax, in two consecutive protocols: first in [ca2+]o ranging from 0.45 to 2.25 mm, and then in [ca2+]o 2.25 mm before, during, and after ...	1991	1990903
intracellular po2 in individual cardiac myocytes in dogs, cats, rabbits, ferrets, and rats.	myoglobin (mb) saturation in individual subepicardial myocytes was determined by cryospectroscopy in dogs, cats, ferrets, rabbits, and rats. mb saturation within 800 microns of the epicardium is not affected by quick freezing or absorption of light by cytochromes. the po2 in equilibrium with mb (pmbo2) was calculated from the mb oxydissociation curve. the minimum pmbo2 found among the 1,000 cells examined was 2.5 torr, at least five times the critical po2 for cytochrome turnover in myocardium. t ...	1991	1996695
differential regulation of brain aromatase by androgen in adult and fetal ferrets.	the contribution of androgens to the regulation of aromatase activity (aa), measured by quantifying the in vitro formation of [3h]estrone from 19-[3h]hydroxyandrostenedione precursor, was studied in equivalent microdissected brain regions of adult and fetal ferrets. in adulthood, aa was similar in the bed nucleus of the stria terminalis, medial (m) and lateral (l) preoptic area (poa), medial (ma) and lateral amygdala (la), ventromedial hypothalamus (vmh), and parietal cortex of gonadectomized ma ...	1991	1999145
method for studying arterial wave transmission effects on left ventricular function.	a technique for studying the real-time effects of arterial wave reflections on the performance of the isolated left ventricle was investigated. real-time arterial loading of an isolated ferret heart with an asymmetric t-tube wave transmission model was obtained with the use of a multiprocessor computer control system and a volume control linear motor pump. the multiprocessor computer system was programmed to compute the instantaneous aortic flow from the instantaneous ventricular pressure. the t ...	1991	2000959
tetrodotoxin does not block the epithelium-dependent release of prostaglandin e2 induced by electrical field stimulation in isolated ferret trachea.	electrical field stimulation (efs) has previously been shown to induce the release of prostaglandin (pg) e2 from ferret tracheal epithelium. we have now conducted a study to see whether this effect of efs is due to the activation of nerves or whether it is a non-neural effect. the release of pge2 and 6-keto-pgf1 alpha into the bath fluid was assayed in isolated ferret tracheas with (e+) or without (e-) epithelium, stimulated by either efs or direct vagal nerve stimulation (dns) repeatedly for 12 ...	1991	2001290
nature of the endogenous pyrogen (ep) induced by influenza viruses: lack of correlation between ep levels and content of the known pyrogenic cytokines, interleukin 1, interleukin 6 and tumour necrosis factor.	fever in influenza results from the release of endogenous pyrogen (ep) following virus-phagocyte interaction and its level correlates with the differing virulence of virus strains. however, the different levels of fever produced in ferrets by intracardial inoculation of ep obtained from the interaction of different virus strains with ferret of human phagocytes did not correlate with the levels of interleukin 1 (il-1), il-6 or tumour necrosis factor in the same samples as assayed by conventional ...	1991	2005436
effects of glucose on hypoxic vasoconstriction in isolated ferret lungs.	to characterize the effects of glucose on the pulmonary vascular response to anoxia and hypoxia, isolated ferret lungs were ventilated with 28% o2 and 5% co2 and perfused at constant flow (100 ml.kg-1.min-1). perfusate glucose concentrations were allowed to fall spontaneously to less than 1 mm (low glucose) or were controlled at 5-6 mm (normal glucose) or 12-17 mm (high glucose). at 60, 120, and 180 min of perfusion, the inspired o2 tension (pio2) was reduced to 0, 10, or 30 torr for 30 min, and ...	1991	2010403
effects of cocaine on excitation-contraction coupling of aortic smooth muscle from the ferret.	the mechanism by which cocaine alters vascular tone is not fully understood. we determined the effects of cocaine on excitation-contraction coupling of isolated ferret aorta. cocaine in concentrations less than or equal to 10(-4) m caused a contractile response in a dose-dependent manner. the response of control muscle was significantly larger than that in muscle from ferrets pretreated with reserpine. cocaine-induced contraction was not affected by endothelial factors, but was significantly inh ...	1991	2010545
intracellular calcium and ventricular fibrillation. studies in the aequorin-loaded isovolumic ferret heart.	to elucidate the role of changes in [ca2+]i in the induction of ventricular fibrillation (vf), ca2+i signals, epicardial electrical potentials, and isovolumic left ventricular pressure were simultaneously recorded in isolated intact ferret hearts loaded with aequorin, a bioluminescent protein. when the preparations were perfused with 3 microm acetylstrophanthidin and 8 mm ca2+, or with a low na+ solution (18 mm na+, 100 mm li+), spontaneous transitions to the vf state were consistently observed ...	1991	2018996