Membrane Of Cat Research Articles

Transplantation of amniotic membrane‐derived multipotent cells ameliorates and delays the progression of chronic kidney disease in cats

Chronic kidney disease (CKD) is a common clinical condition in domestic cats, characterized by tubulointerstitial, vascular and glomerular inflammation and severe fibrosis. Studies in rodent model of induced CKD have shown a decrease and stabilization of the clinical condition. In this study was evaluated the safety and effect of intrarenal and intravenous infusion of allogeneic mesenchymal stem cells (AMSCs) derived from feline amniotic membrane in cats with naturally occurring CKD. Cat AMSCs were harvested after mechanical and enzymatic digestion of amnion. A healthy cat received intrarenal injection of AMSCs guided by ultrasound in both kidneys (5×105 cells/kidney). Nine cats with CDK received repeated intravenous infusions of AMSCs (2×106 cells×2 treatments). The clinical parameters of healthy cat did not change, but sedation and general anaesthesia was required. The number of interventions stressed the animal, and he developed transient haematuria after AMSC injection. Cats with CDK registered a significant improvement of renal function (decrease in serum creatinine and urine protein concentrations and increase in urine specific gravity). The kidney architecture and morphology did not change following the treatment. The feline AMSCs have a renoprotective effect and improve renal function in cats with naturally occurring CKD, stabilizing the clinical condition and disease progression. Thus, intravenous injection of AMSCs may be an important tool to provide welfare in cats with chronic kidney disease.

Ocular counterrolling in response to static and dynamic tilting: Implications for human otolith function

Nineteen subjects underwent rotation about the naso-occipital axis to examine ocular counterrolling (OCR) responses in both dynamic and static conditions. Dynamic rotation consisted of tilt to 90 degrees right and left at constant velocity of 3 degrees /s, with acceleration at 0.2 degrees /s(2). Static rotation (stepwise tilting) consisted of one minute at steps 30 degrees, 60 degrees, 90 degrees, 60 degrees, 30 degrees to each side. OCR amplitudes at each of the above head tilts in dynamic vs. static tilt showed highly significant differences, with dynamic tilt exceeding that of static. Although OCR disconjugacy was greater in static than dynamic in most subjects, that difference was not statistically significant. Possible explanations for the disparity in the responses to dynamic and static tilt in humans lie in vestibular experiments leading to the conclusion that the otolith membrane in cats moves not as a unit, but rather in patches (28). This is supported by work showing the otolith membrane in bullfrogs does not move en bloc (1). In addition, hair cell responses are found to be amplified during motion as compared to the responses during static positioning (20). Functionally, it is suggested that the otolith system may perform better in moving than in static conditions.

Experimental infection of cats with Chlamydophila felis.

Cats experimentally infected with a British isolate of Chlamydophila felis (C. felis), B166 strain, by droplet into the eye and nose developed conjunctivitis, mild rhinitis and fever. The chlamydophila were first isolated from conjunctiva, nictitating membrane and then from lung, tonsil, liver, spleen, kidney, nasal and vaginal swabs and blood. These results indicate that C. felis B166 strain first infected and replicated in the conjunctiva and nictitating membrane in cats with symptoms which were mostly limited to conjunctivitis, and then pervaded the whole body by bacteremia.

Dimensions of and vibrations in the round window membrane in cats.

The shape and size of the round window membrane and its vibratory pattern were investigated in cats by use of an optical displacement meter and time-averaged holography. The round window membrane is convex toward the scala tympani and appears to be almost elliptic in shape. The major and minor axes of the membrane are 2,273 and 1,934 microns. The mean degree of convexity is 1,975 microns. Under vibration the area of maximum displacement occurs anteriorly-superiorly at low frequency. As frequency is increased, the maximum displaced area shifts posteriorly-superiorly, then breaks up into several segments.

Dimensional study and vibratory pattern of the round window membrane in cats

Dimensional study and vibratory pattern of the round window membrane in cats

Calcium antagonism of the inhibitory effects of fentanyl on the contraction of the nictitating membrane in cats

The contractile responses elicited from the nictating membrane of cats by postganglionic sympathetic nerve stimulation were decreased by fentanyl (10–20 μg/kg injected in the lingual artery). The inhibitory effect of fentanyl was preferential on responses elicited bu low frequency stimulation. Fentanyl (10–25 μg/kg) did not change the contractile responses to noradrenaline and tyramine. The inhibitory effect of fentanyl was antagonized by naloxone. Increases in plasma calcium concentration did not alter the contractile responses to symphatetic nerve stimulation but antagonized the inhibitory effect of fentanyl in a dose-depedent manner suggesting a possible competitive antagonism.

The effect of (D-Ala 2)-met-enkephalin on the contraction of nictitating membrane in cats

The effects of (D-Ala 2)-Met-enkephalin (DAME) on the nictitating membrane contraction induced by either cervical sympathetic nerve stimulation or i.v. administration of norepinephrine were assessed in anesthetized cats. The contraction induced by sympathetic nerve stimulation (0.5–16 Hz) was greatly reduced by pretreatment with DAME (300 μg/kg, i.v.). The reduction due to DAME was readily reversed by administration of naloxone (1 mg/kg, i.v). The contraction, enhanced after administration of cocaine, was also suppressed by DAME. Om the other hand, the contraction induced by i.v. application of norepinephrine was unaffected by DAME pretreatment. The results indicate that DAME exhibit a morphine-like effect of the contraction of the nictitating membrane.

Autonomic ganglion-blocking action of surugatoxin isolated from the Japanese ivory shell (Babylonia japonica)

Pharmacological properties of the surugatoxin from Japanese ivory shell (Babylonia japonica) (Kosuge et al. 1972, Gohgi et al. 1973) were studied, and its properties were compared with those of IS-toxin (Hirayama et al. 1970, 1972, Gohgi et al. 1973) isolated from the same shell. Surugatoxin (0.15_??_0.2mg/kg i. v.) reduced spontaneous movement, causing a drowsiness, mydriasis and relaxation of nictitating membrane in cats. The toxin had no effects either on the neuromuscular junctions or on the striated and smooth muscles. Contractile responses of the guinea-pig ileum preparations to nicotine (1×10-7g/ml) were observed, and the responses to nicotine were abolished by hexamethonium (C6, 4×10-4g/ml). Surugatoxin, on the other hand, at a concentration of 1×10-7_??_1×10-6g/ml reduced or eliminated the responses to nicotine and to 1, 1-dimethyl-4-phenylpiperazium iodide (DMPP, 1×10-6g/ml), but the contractile responses due to 4-(m-chlorophenyl-carbomyloxy)-2-butynyltrimethylammonium chloride (McN-A-343, 1×10-5g/ml) were scarcely effected by the toxin at the same concentrations. The toxin was assumed to have a ganglionic blocking action in the inner plexus of the intestine. Accordingly, effect of the toxin on the superior cervical sympathetic ganglion of cats was studied using the Trendelenburg method (1954, 1956). Surugatoxin injected into the femoral vein (150_??_200μg/kg) or the lingual artery (40_??_50μg/kg, to the ganglion) decreased or abolished the contractile responses of the nictitating membrane and the post-ganglionic external potentials to an electrical stimulation of the pre-ganglionic nerve. Surugatoxin did not however, alter responses to the post-ganglionic nerve stimulation. Injection of surugatoxin (40_??_50μg/kg, to the ganglion) reduced or eliminated contractions of the nictitating membrane due to 2μg/kg of DMPP (to the ganglion), a nicotinic ganglionic stimulant (Chen et al. 1951, 1953) and to 25μg/kg of candicine, a ganglionic stimulant (Urakawa et al. 1959, Deguchi et al. 1963), while the contractions due to 2.5_??_5μg/kg of McN-A-343 (to the ganglion), a muscarinic stimulant (Raszkowski, 1961) were scarcely effected by the toxin with the same dose. When 40_??_50μg/kg of surugatoxin was administered (to the nictitating membrane), it affected neither the responses of nictitating membrane nor the pressor responses of systemic blood pressure induced by norepinephrine (5μg/kg, to the nictitating membrane). The potency of surugatoxin, determined in a manner similar to that described by Gyermek (1957) was about 6 times as strong as that of hexamethonium. It is suggested, that the mode of ganglioplegic action of the surugatoxin is similar to that of IS-toxin (Hirayama et al. 1972), which may be due to an inhibitory action on the nicotinic ganglionic receptors in the inner plexus of the intestine and in the superior cervical nerve. Surugatoxin may be a specific inhibitor on the nicotinic ganglionic receptors in autonomic ganglia.

Amino acid composition of cat and human erythrocyte membranes

1. 1. Amino acid composition of cat and human erythrocyte membranes prepared simultaneously was investigated. 2. 2. No differences in amino acid concentrations were detected in these two species. 3. 3. Cat membranes contained less than one-half of the glucosamine concentration found in human membranes.

神経節遮断効果を有するAmidinothiocholine系化合物の作用様式の解明

2-trimethylaminoethyl-1'-ethylisothiuronium bromide hydrobromide (ETMA) produced a marked fall in the blood pressure of anesthetized cats. This action was not antagonized by atropine. Pressor response to adrenaline in cats and inhibitory response to electrical stimuli in Finkleman preparation of isolated rabbit jejunum were not blocked. ETMA, however, blocked blood pressure response to nicotine, to occlusion of the carotid arteries and to stimulation of the cardiac end of the cut right vagus. The contraction of the nictitating membrane in cats produced by stimulation of the preganglionic fiber, administration of DMPP (i. a.) and MTMA (i. a.) was blocked by intra-arterial injection of ETMA. The response to stimulation of the postganglionic fiber, adrenaline (i. a.) and KCl (i. a.) was not affected. These results suggest that the ETMA-induced hypotension could be related to blockade of the autonomic ganglia, presumably acting on the ganglion cell at the postsynaptic cholinoceptive site.

Validation of Holographic Observations on the Displacement of the Tympanic Membrane in Cats

Previous experiments, using time-averaged holography [J. Acoust. Soc. Amer. 47, 60 (1970); 48, 112 (1970)], had strongly suggested that the displacement of the tympanic membrane, at least in fresh cadavers, obeys the “curved-string” principle of Helmholtz rather than the “stiff-plate” concept of von Békésy. These unexpected findings required further evaluation of the experimental procedure. (1) The tympanic membrane had been widely exteriorized for holographic purposes: Round-window cochlear microphonic recordings provided correcting factors for the SPLs measured at the membrane. (2) The membrane had been coated for proper reflectance: Further microphonic experiments demonstrated no measurable effects upon middle-ear transmission. (3) Fresh cadaver specimens had provided maximal holographic resolution by minimizing thermal agitation and minute movement: Additional obsevations in living cats altered the resolution, but not the results. These and other, earlier, evidence argue emphatically the validity of the holographic observations. [Supported by several NIH grants.]

Pharmacological actions of amidinothiocholine derivatives. 3. The effects of amidinothiotriethylcholine derivatives on autonomic nervous system

Pharmacological properties of 2-triethylaminoethylisothiuronium bromide hydrobromide (TEAEI), 2-triethylaminoethyl-1'-methylisothiuronium bromide hydrobromide (MTEAI), and 2-(2'-triethylaminoethylthio)imidazoline bromide hydrobromide (ETEAI), derivatives of amidinothiotriethylcholine, on autonomic nervous system were examined. These compounds showed depressor action and blocked the pressor action induced by DMPP and nicotine in rats and cats. The pressor response to adrenaline and Finkleman preparation of isolated rabbit jejunum was not blocked. Contraction of nictitating membrane in cats induced by electrical stimulation and nicotine is blocked by these compounds. TEAEI and ETEAI showed a weak negative inotropic action on the heart preparation of a guinea pig but MTEAI showed a biphasic action. Stimulating action on the isolated guinea pig ileum induced by these compounds was blocked by papaverine but not by atropine. These compounds caused a weak vasocontriction on isolated perfused rabbit ear. Contraction of vas deferens of a guinea pig induced by electrical stimulation of preganglionic fiber of hypo gastric nerve was inhibited by these compounds but contraction induced by transmural stimulation was not altered. Acute toxicity of in mice was also tested.

Effects of angiotensin on the autonomic nervous system

T he physiological role and mechanism of action of angiotensin continue to excite the interest of a large number of workers. Angiotensin has at least three different effects: it causes contraction of a variety of smooth muscles, especially of vascular origin ; it increases the rate of secretion of aldosterone in a wide range of animal species; it has effects at various sites of the autonomic nervous system. The first of these actions to be described was the effect as a direct vasoconstrictor which occupied the attention of cardiovascular investigation until the late 1950’s. Since then its two other types of action have excited renewed interest among research workers but the results in the two fields of work provide an interesting contrast. The autonomic effects of angiotensin are complex and their physiological role is still obscure, whereas the effect on aldosterone secretion is well defined and appears to be of physiological importance in the control of blood volume. The first firm evidence that angiotensin could activate the autonomic nervous system in the intact animal was provided by the experiments of Renson and associates’ who in 1959 demonstrated that angiotensin could cause contraction of the nictitating membrane in cats (whose nerve supply is exclusively adrenergic) ; this action was blocked by the alpha-adrenergic blocking agent, phenoxybenzamine. Since then a great deal of work has been done in this field, and it is therefore somewhat surprising that no clear picture has emerged as to the physiological role of these effects, i.e., what part they might play in the response to angiotensin generated in the blood stream by endogenous renin. Nevertheless, these effects are interesting and it is worth discussing them in some detail to illustrate how extremely complex the effect of angiotensin can be. The references cited are not necessarily the earliest ones, but have been selected as important ones which also give further references to much of the earlier literature. The effects which have been so far described fall into the following groups: (1) parasympathomimetic effects and potentiation of the effects of cholinergic nervous activity; (2) activation of sympathetic ganglia; (3) stimulation of catecholamine secretion from the adrenal medulla; (4) potentiation of the effects of adrenergic nerve stimulation ; (5) sympathomimetic effects due to an action on the brain; and (6) inhibition of parasympathetic nerves to the heart by an effect on the brain. In considering the possible physiological role of such effects, it is most important to bear in mind the concentration of angiotensin necessary to produce these effects and to compare this with those known to occur spontaneously in response to changes

Vibrational Holography of the Tympanic Membrane in Cats

Vibrational holography (Powell and Stetson, 1965) was applied to a study of the vibratory characteristics of the cat's tympanic membrane (TM). Technical difficulties were presented by the TMs small size, low stiffness, and its transparency. Vibrational holograms of the TM for various frequencies and sound-pressure levels are demonstrated. These holograms are pictures of the TM with superimposed isoamplitude contour lines. The first line appears at a peak amplitude of 1.2×10−5 cm, below which vibrations cannot be discerned. Measurements may be extended over a range of approximately 20 dB. Results may be summarized as follows: (1) Vibratory patterns remain essentially unchanged in the first mode up to a frequency of 2000 Hz, with higher modes occurring above that value; (2) at all frequencies, the TM vibrates maximally in the posterior quadrant, less in the anterior, and least in the inferior quadrant; (3) for a uniform amplitude of the TM at its point of maximal displacement, mallar displacements increase first with frequency and decrease steeply at frequencies above 2000 Hz. [Supported by NIH grants.]

A new ganglion-stimulating compound: 2-imino-1,3-diaza-4-carboxyethyl cycloheptane hydrochloride (OG 30)

Out of a number of compounds tested for cardiovascular activity, 2-imino-1, 3-diaza-4-carboxyethyl cycloheptane hydrochloride (OG 30) was found to produce an increase in blood pressure and a contraction of the nictitating membrane in cats. The above effects elicited by i.v.-administered OG 30 were either blocked or reduced by phentolamine, hexamethonium, guanethidine, N-N-diisopropyl-N′-isoamyl-N′-diethylaminoethyl urea hydrochloride (P-286), reserpinization and bilateral sympathectomy, but were not appreciably affected by cocaine, hemicholinium, atropine, spinal section or bilateral adrenalectomy. Thus it must be inferred that the compound caused a release of catecholamines largely by stimulation of the sympathetic ganglia. Ganglion-stimulating action was confirmed when the compound was injected directly to the superior cervical ganglion. The stimulant action on the parasympathetic ganglia though weaker, was also observed in dogs and in isolated guinea pig ileum. Hemicholinium was unable to block the contraction of the cat nictitating membrane in response to OG 30 and 1,1-dimethyl-4-phenyl-piperazinium iodide (DMPP) administered directly to the superior cervical ganglion at a time when it had blocked the contraction of the membrane elicited by preganglionic sympathetic nerve stimulation. This observation conflicts with the participation of cholinergic link in the postganglionic adrenergic transmission in the nictitating membrane. OG 30 DMPP Ganglion-stimulation Adrenergic transmission Nictitating membrane Hemicholinium

Dual actions of some N-(1-phenylethyl)guanidines on the nictitating membrane of conscious cats

Abstract After 6 hr, high doses (10 or 20 mg/kg) of some adrenergic neuron blocking drugs derived from N-(1-phenylethyl)guanidine produce relaxation of the nictitating membranes of conscious cats which is less than that produced by small doses (2.5 or 5 mg/kg). After 24 hr, there were marked responses to some drugs that had produced little effect after 6 hr. High doses of the drugs contract the nictitating membranes of cats treated with pempidine or (—)-N-(1-phenylethyl)guanidine; low doses do not. This contraction opposes the relaxation evoked by the adrenergic neuron blockade and could account for the anomalous dose-response relationships. The contraction may result from localized release of noradrenaline from the nictitating membrane.

Potentiation of inhibitory and excitatory effects of catechol amines by bretylium.

Enhancement of both excitatory and inhibitory responses to adrenaline, noradrenaline and isoprenaline was demonstrated with bretylium both in vivo and in vitro. Excitatory responses studied included rise of blood pressure and contraction of the nictitating membrane in cats and the contraction of aortic strip in rabbits; the inhibitory responses studied were fall of cat blood pressure and relaxation of rat uterus and rabbit tracheal chain. Possible mechanisms of potentiation of the effects of catechol amines by bretylium are discussed. A sensitization of the peripheral effector cells is suggested as a likely mechanism of potentiation.

Histochemical investigations of the “Kul' chitskii cells” in the gastrointestinal tract of experimental animals

The authors conducted a histochemical study of the distribution of “Kul' chitskii cells” and their saturation with the granules in various laboratory animals. The argentaffin and chromaffin reaction were determined with a parallel diazo reaction. An uneven distribution of “Kul'chitskii cells” along the intestine was revealed. The highest density of the cells and the greatest granule saturation were observed in the duodenal mucous membrane of cats, rabbits, guinea pigs, white rats, white mice, monkeys and chicks. The content of argentaffin granules is slightly decreased in the cellular protoplasma of fasting guinea pigs, but even in animals dead of hunger they do not disappear completely. After intraperitoneal injection of reserpine, argentaffin granules vanish in normal animals, but not in fasting ones.

CLINICAL AND EXPERIMENTAL STUDY UPON RAUWOLFIA SERPENTINA ALKALOIDS

I. Using dogs, cats and rabbits, there were examined mainly, the circulatory actions of R.s. and Deserpidine. Results are as follws.1. The lowering of arterial blood pressure due to R.s. is of mild and slow mode; however it is possible to exist such cases which show the abrupt response by the intravenous use of Alseroxylon solved in propylenglycol. This abrupt reaction does neither depend upon nature of solvents, nor upon so-called yohimbine-liked action of R.s., 2. R.s. suppresses carotid sinus pressor reflex, but does not inhibit its depressor reflex.3. In cats, R.s. does not ameliorate the elevation of blood pressure due to faradization of peripheral end of splanchnicus, but the stimulation of the central end.4. R.s. does not inhibit pressor action of epinephrine by means of single intravenous injection nor of droplets-infusion.5. Reserpine does not influence the contraction of nictating membrane in cats induced by faradization of preganglionic fiber of upper cervical sympathetic ganglion.6. The miosis can be brought on by the intravenous application of R.s.; in turn, atropine changes this miosis into mydriasis.7. Blood pressure moderators were cut previously; no striking lowering of arterial pressure can be observed in decerebrated dogs even 15 minutes after the intravenous injection of Reserpine, whereas, 1-Hydrazinophthalazine shows marked lowering of blood pressure within this time course.8. R.s. is apt to set up bradycardia: slight prolongation of PQ interval and respiratory sedation, although these data can be often attributable to the tranquil state of animals.9. The circulatory analyzis clarifies that the decreas in W. (peripheral vascular resistance), E′. (elastic resistance), and the increase in S.V. (stroke volume), M.V. (minute volume) can be determined before the lowering of blood pressure does not remarkably stilly appear.10. The experimental results obtained with the use of Deserpidine are similar to those of Reserpine.II. Effects of lowering of blood pressure and influence on circulatory dynamics were examined in 87 patients suffering from high blood pressure, especially from essential hypertension under the treatment with R.s..1. With the parenteral use of large dosis the lowering of blood pressure is so remarkable that shock and severe side effect can appear, though it happens not frequent. At this depression the hemodynamics is characterized with the decrease in both W. and E′ and with the increase in M.V., When B.P. is excessively lowered, the hemodynamics designs to disclose so-called “Anspannungskollaps”.2. The effect of lowering of B.P. can be ascertained of usual dosage. The earlier is the stage of disorder, classified by Keith-Wagener, the more valid is R.s.. Improvement of subjective claim is not necessary parallel to the degree of lowering of B.P., and the former is generally more striking. The side effect is not so severe that it does not disturb the daily life of patients; but it was, evan if not often, observed that it increases in frequency of anginal attack, or induces cardiac block e.g. partial sinuauricular block.3. As to Alseroxylon, common dosage is thought to be 6-8mg. pro die, and as Reserpine, it is assumed to be enough only 1/8-1/10 of the dosage in Alseroxylon treatment. In the patients who show no effective lowering of B.P. within this dosage, there cannot be expected more marked lowering even if with madication of larger dosis above this limit. The patients who show refractoriness against R.s., are apt to disclose side effect.4. The changes of circulatory dynamics in peroral and chronic use are variable from case to case. There can be seen frequently the increase in M.V. though it is of slight extent. In the type of W. or E′., R.s. affects to induce normal state.5. The influence of R.s. upon R.B.F. (renal blood flow) or T.R.R. (total renal resistance) is not constant, and there

イソニコチン酸ヒドラジツト (INAH) の血壓作用, 特に二次的血壓急騰の成立機序に關する實験的研究

INAH in large toxic doses produces a slight fall in blood pressure which is followed by a sudden rise of blood pressure accompanied invariably by convulsions and a contraction of nictitating membrane in cats. The aforesaid rise of pressure and contraction of nictitating membrane are neither inhibited by atropine nor by d-tubocurarine, but by benzylimidazoline and TEAB. The convulsions, however, are depressed by d-tubocurarine, but not by benzylimidazoline or TEAB. Convulsions and the rise of blood pressure are 136th depressed to a certain extent by deep narcosis and completely by decapitation. The results lead to the following conclusions : INAH in large doses causes central nervous system stimulation, resulting in convulsions. The rise, of blood pressure results from stimulation of sympathetic vasoconstrictor centre.