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Aisa J, Lahoz M, Serrano PJ, Junquera C, Peg MT, Vera-Gil A. Intrinsic innervation of the chicken lower digestive tract. Neurochem Res 1997; 22:1425-35. [PMID: 9357006 DOI: 10.1023/a:1021990025420] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We have studied the different components of the enteric nervous system in the rectum and cloaca of the chicken by means of histochemical and immunohistochemical techniques. We found cholinergic neuronal bodies as well as nervous fibers, which constitute part of the Meissner and Auerbach plexuses. We also observed plentiful catecholaminergic fibers in both plexuses, though there were no catecholaminergic neuronal bodies. With respect to the Vasoactive Intestinal Peptide (VIP) and substance P (SP) positive peptidergic innervation, only positive fibers were found, which were less abundant than in the other zones of the gastrointestinal tract. The optic microscopy results were confirmed by electron microscopy.
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Affiliation(s)
- J Aisa
- Dpto. de Ciencias Morfológicas, Facultad de Medicina de Zaragoza, Spain.
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Atoji Y, Hirasawa Y, Yamamoto Y, Suzuki Y. Distribution of neurotensin-immunoreactive neurons in the digestive tract of the chicken. JOURNAL OF THE AUTONOMIC NERVOUS SYSTEM 1995; 53:185-94. [PMID: 7560755 DOI: 10.1016/0165-1838(94)00172-g] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The origin of the neurotensin-containing nerve fibers in the digestive tract of the chicken has been investigated with the use of colchicine and immunohistochemistry. Neurotensin-immunoreactive nerve fibers were found in the smooth muscle layers from the esophagus to the duodenum. Their density of distribution was very high in the esophagus and crop (maximum mean value: 1315/mm2 of sectional area in the lamina muscularis mucosae of the crop) and decreased progressively to the duodenum. Neurotensin-immunoreactive neuronal cell bodies were observed after colchicine treatment in the submucosal plexuses of the esophagus and crop and in the myenteric plexuses of the esophagus, crop, proventriculus and gizzard, and they extended varicose fibers. The number of neurotensin-immunoreactive cell bodies was high in the myenteric plexus of the gizzard (28.3 +/- 2.7/ganglion) but low in the plexuses of the esophagus, crop and proventriculus. Seven days after cutting the glossopharyngeal nerve and vagus nerve unilaterally, the number and extent of neurotensin-immunostained structures in the smooth muscle layers from the esophagus to the gizzard did not show any significant difference between operated and unoperated sides. These results indicate that in the chicken the great majority of neurotensin-immunoreactive enteric fibers originate in the intramural plexuses of the upper digestive wall and are mainly distributed to smooth muscle cells.
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Affiliation(s)
- Y Atoji
- Laboratory of Veterinary Anatomy, Faculty of Agriculture, Gifu University, Japan
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Neural and smooth muscle development in the chicken gizzard. ACTA ACUST UNITED AC 1995; 204:271-275. [DOI: 10.1007/bf00208494] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/1994] [Accepted: 10/21/1994] [Indexed: 11/25/2022]
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Ohashi H, Takewaki T, Unno T, Komori S. Development of vagal innervation to the muscle of the avian gizzard. JOURNAL OF THE AUTONOMIC NERVOUS SYSTEM 1993; 42:233-40. [PMID: 8459097 DOI: 10.1016/0165-1838(93)90368-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The development of the vagal innervation to the gizzard has been investigated in chick embryos and young chicks. The membrane potential, first measurable on the 15th day of incubation, was -54 +/- 0.5 mV and increased with development to -67 +/- 0.4 mV. The latter value was attained 5 days after hatching and persisted thereafter. Stimulation of intramural nerves elicited a cholinergic, excitatory junction potential (EJP) for the first time, only in a small fraction of cells, on the 20th day of incubation. Within 3 days after hatching, cholinergic transmission showed the same features as in older chicks. Stimulation of the vagus nerve elicited no membrane potential responses before hatching but as early as 4 days after hatching, non-adrenergic, inhibitory junction potentials (IJPs) were evoked. In the next 10 days or so, the IJP was replaced with a cholinergic EJP as seen in mature tissues. After atropine (0.1-1 microM) treatment, both vagal and intramural nerve stimulation evoked a non-adrenergic IJP in a small fraction of cells immediately after hatching. The fraction of cells exhibiting the IJP increased with growth and reached 100% 5 days after hatching. Hexamethonium (50 or 100 microM) abolished the vagally-evoked EJPs. The vagally-evoked IJPs remained unchanged after application of hexamethonium in the early days after hatching, but later they were abolished in about half of the cells.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- H Ohashi
- Department of Veterinary Science, Faculty of Agriculture, Gifu University, Japan
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Gabella G, Halasy K. On the nerve plexus of the chicken gizzard. ANATOMY AND EMBRYOLOGY 1987; 177:97-103. [PMID: 3434849 DOI: 10.1007/bf00572533] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The Auerbach's plexus of the gizzard was stained in toto in adult chicken and in young and newly-hatched chicks. The plexus lies immediately beneath the serosa and extends over 55% of the surface of the organ, covering its cranial and caudal poles and the two curvatures. The areas into which the plexus does not extend (i.e., most of the ventral and the dorsal surface) are those where the muscle is covered by the laminar tendon of the gizzard. The ganglia are large, often with hundred of neurons, and have short and broad connecting strands. They are surrounded by a capsule of connective tissue. The ganglion neurons are discoidal and in the adult they measure up to 50 microns in diameter, each being surrounded by a set of glial cells. A few small neurons persist in the adult; in the newly-hatched chick these are predominant, but some large neurons up to 25 microns in diameter are already present. The ultra-structural features of the ganglia of the Auerbach's plexus include the abundance of axo-somatic synapses, as well as numerous axo-dendritic synapses, the presence of intra-ganglionic bundles of collagen fibrils and blood vessels, the abundance of glial cells. In addition to the plexus beneath the serosa, the gizzard has many small intramuscular ganglia located throughout the musculature (which is exclusively circular). These ganglia do not have a connective tissue capsule and are made of small and tightly packed neurons.
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Affiliation(s)
- G Gabella
- Department of Anatomy and Embryology, University College London, United Kingdom
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Kitazawa T, Temma K, Kondo H. Presynaptic alpha-adrenoceptor mediated inhibition of the neurogenic cholinergic contraction in the isolated intestinal bulb of the carp (Cyprinus carpio). COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. C, COMPARATIVE PHARMACOLOGY AND TOXICOLOGY 1986; 83:271-7. [PMID: 2871988 DOI: 10.1016/0742-8413(86)90122-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The effects of norepinephrine, epinephrine and clonidine on neurogenic cholinergic contraction were examined in the presence of a beta-adrenoceptor blocking agent, carteolol (5 X 10(-6) M), in the isolated intestinal bulb of the carp. Norepinephrine, epinephrine (10(-9)-10(-6) M) and clonidine (10(-8)-10(-5) M) inhibited the contraction induced by low frequency (2 or 5 Hz) transmural stimulation (TMS) without inhibiting the contraction induced by acetylcholine (ACh, 6 X 10(-8)-4 X 10(-7) M). Methoxamine (10(-4) M) and phenylephrine (10(-4) M) showed no such inhibitory effect on the TMS-induced contraction. The inhibitory effects of catecholamines and clonidine were decreased by phentolamine (5.4 X 10(-6) M) and yohimbine (10(-7)-10(-6) M) but not by prazosin (7 X 10(-7)-10(-6) M). Nicotine (10(-6)-10(-4) M) and serotonin (3 X 10(-8)-3 X 10(-6) M) caused contraction of the intestinal bulb indirectly by releasing endogenous ACh. This contraction was inhibited by norepinephrine, epinephrine and clonidine in a concentration-dependent manner. The present results suggest that catecholamines and clonidine inhibit cholinergic transmission via the activation of a presynaptic alpha-adrenoceptor (presumably of alpha-2 type) located on the cholinergic nerve terminals innervating the smooth muscle of the intestinal bulb of the carp.
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Kitazawa T, Furuhashi H, Umezawa K, Morioka M, Temma K, Kondo H. Is there functional cholinergic innervation in the frog duodenum (Rana catesbeiana)? COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. C, COMPARATIVE PHARMACOLOGY AND TOXICOLOGY 1986; 85:275-82. [PMID: 2879686 DOI: 10.1016/0742-8413(86)90194-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
To determine if functional cholinergic innervation occurs in the frog duodenum or not, the effects of exogenous acetylcholine and electrical transmural stimulation, the contractile activity of an acid extract from the frog duodenum, and the distribution of acetylcholinesterase (AChE) activity in the wall of the frog duodenum were investigated. Acetylcholine caused non-sustained contraction in a dose-dependent manner (100 nM-1 mM). The ED50 value was 17 +/- 2.4 microM. Atropine (500 nM) shifted the dose-response curve for acetylcholine parallel to the right. Transmural stimulation of the frog duodenum caused frequency-dependent (0.5-50 Hz) contraction which was not decreased by atropine (500 nM) at all. The acid extract from the frog duodenum caused contraction of a longitudinal muscle strip of guinea-pig ileum but atropine (500 nM) had no significant effect on the contraction. Only a little AChE activity was found in Auerbach's plexus of the frog duodenum compared with that of the rat ileum. These results suggest that a cholinergic nerve is present in the frog duodenum but its physiological significance is very small.
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Saffrey MJ, Polak JM, Burnstock G. Distribution of vasoactive intestinal polypeptide-, substance P-, enkephalin and neurotensin-like immunoreactive nerves in the chicken gut during development. Neuroscience 1982; 7:279-93. [PMID: 6176901 DOI: 10.1016/0306-4522(82)90166-x] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The ontogeny and distribution of nerve cell bodies and fibres which contain vasoactive intestinal polypeptide-, substance P-, enkephalin- and neurotensin-like immunoreactivity have been studied in the chicken gastrointestinal tract, using immunocytochemistry. All four peptides were found in nerve fibres, with characteristic distribution patterns, which, in the cases of vasoactive intestinal polypeptide, substance P and methionine enkephalin were similar to those described for the mammalian gut. In addition, many of these fibres were shown to arise from intrinsic neurons, since immunoreactive nerve cell bodies for each of the peptides studied were observed. Neurotensin-immunoreactive nerves were confined to the upper part of the tract and neurotensin immunoreactive cell bodies were only observed in embryonic and newly hatched chicken gut. All four peptides were first observed at 11 days of incubation, or Hamburger-Hamilton stage 37, 20 in the upper part of the tract, particularly in the gizzard. Substance P and methionine enkephalin were subsequently seen in more caudal regions, while vasoactive intestinal polypeptide developed from each end of the tract. Adult patterns of immunoreactivity in nerve fibres were achieved during the first week after hatching. A striking observation was that immunoreactive neuronal cell bodies were much more abundant in the gut of young chickens and chicken embryos than in that of adult birds.
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Ali HA, McLelland J. Neuron number in the intestinal myenteric plexus of the domestic fowl (Gallus gallus). Anat Histol Embryol 1979; 8:277-83. [PMID: 159646 DOI: 10.1111/j.1439-0264.1979.tb00813.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Seno N, Nakazato Y, Ohga A. Presynaptic inhibitory effects of catecholamines on cholinergic transmission in the smooth muscle of the chick stomach. Eur J Pharmacol 1978; 51:229-37. [PMID: 213291 DOI: 10.1016/0014-2999(78)90408-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In the vagus nerve--smooth muscle preparation isolated from the chick proventriculus, adrenaline, clonidine (10(-8) - 2.5 x 10(-7) M), noradrenaline (10(-7) - 2.5 x 10(-6) M) and dopamine (10(-5) - 10(-4) M) inhibited the contraction induced by low frequency (0.5 Hz) stimulation of the vagus nerve, but they did not inhibit the contraction elicited by acetylcholine (5 x 10(-8) - 5 x 10(-7) M). The concentration producing 50% inhibition was 10(-7) M for adrenaline and clonidine, 10(-6) M for noradrenaline, and 5 x 10(-5) M for dopamine. Isoproterenol (5 x 10(-8) - 5 x 10(-7) M) inhibited the responses induced by both stimulation of the vagus nerve and acetylcholine. The inhibitory effects of the catecholamine and clonidine were blocked by phentolamine (2.7 x 10(-6) M) but not by 5-(3-tert-Butylamino-2-hydroxy)-propoxy-3, 4-dihydrocarbostyril hydrochloride (OPC 1085) which blocked the effect of isoproterenol. It is suggested that presynaptic alpha-receptors are present in the myenteric plexus of the chick proventriculus, and that the catecholamines and clonidine exert their inhibitory effects on cholinergic transmission via these receptors.
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Kyösola K. Comparative formaldehyde-induced and glyoxylic acid-induced fluorescence histochemical studies on the intrinsic adrenergic innervation of the intestine and the liver of normal and vagotomized cats. Acta Histochem 1978; 62:188-99. [PMID: 104525 DOI: 10.1016/s0065-1281(78)80085-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The inbuilt intrinsic adrenergic nervous apparatus of the intestine and liver of the cat was studied using 1. the formaldehyde-induced fluorescence histochemical method and 2. the glyoxylic acid-induced fluorescence histochemical method for serial microtome sections and whole mount tissue layers or smear preparations. In addition, the effect of I) total abdominal infra-diaphragmatic vagotomy with or without associated Finney-type gastro-duodenostomy and II) unilateral (left or right) and bilateral cervical vagotomy with or without tracheostomy on the intrinsic adrenergic innervation was tested. Fluorescing varicose axons, both "free" (i.e. unrelated to the blood vessels) and gathered to typical perivascular nerve plexuses were observed in all segments and all layers of the wall of the intestine. The density of the adrenergic innervation varied remarkably from an area to another, even in the same segment and tissue layer, which makes comparative estimations of the density of the innervation very difficult. However, the intrinsic adrenergic innervation of the circular muscle layer of the colon and the rectum seems to be consistently quite rich, and in the rectum, also the longitudinal muscle layer is relatively heavily innervated. It thus seems obvious that (in the cat) also the direct adrenergic innervation of the external smooth muscle layers is of considerable importance, specially in the rectum. In contrast, the results of the present study clearly indicate that the liver parenchyma (of the cat) is devoid of functional intrinsic adrenergic innervation. Vagotomies did not cause any changes in the intrinsic adrenergic innervation of the intestine and liver: even after complete vagotomy no reduction was observed in the number of fluorescing axons or in the intensity of the fluorescence. Consequently, the vagal contribution of adrenergic axons to the liver and the intestine must be negligible, at least in the cat. The use of the glyoxylic acid-induced fluorescence histochemical method and whole-mount tissue layers was found most suitable for mapping and comparative estimation of the density of the intrinsic adrenergic nerve net, and is therefore recommended for other similar or related studies.
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Alimentary Canal: Anatomy, Prehension, Deglutition, Feeding, Drinking, Passage of Ingesta, and Motility. AVIAN PHYSIOLOGY 1976. [DOI: 10.1007/978-3-642-96274-5_9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Oosaki T, Sugai N. Morphology of extraganglionic fluorescent neurons in the myenteric plexus of the small intestine of the rat. J Comp Neurol 1974; 158:109-19. [PMID: 4430735 DOI: 10.1002/cne.901580107] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Unsicker K. Fine structure and innervation of the avian adrenal gland. 3. Non-cholinergic nerve fibers. ZEITSCHRIFT FUR ZELLFORSCHUNG UND MIKROSKOPISCHE ANATOMIE (VIENNA, AUSTRIA : 1948) 1973; 145:557-75. [PMID: 4774986 DOI: 10.1007/bf00306724] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Bennett T, Malmfors T, Cobb JL. Fluorescence histochemical observations on catecholamine-containing cell bodies in Auerbach's plexus. ZEITSCHRIFT FUR ZELLFORSCHUNG UND MIKROSKOPISCHE ANATOMIE (VIENNA, AUSTRIA : 1948) 1973; 139:69-81. [PMID: 4710502 DOI: 10.1007/bf00307462] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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McKirdy HC, Jones JV, Ballard KJ. Cholinesterase histochemistry of the rabbit distal colon. HISTOCHEMIE. HISTOCHEMISTRY. HISTOCHIMIE 1972; 29:287-95. [PMID: 4115420 DOI: 10.1007/bf00279811] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Furness JB, Costa M. Morphology and distribution of intrinsic adrenergic neurones in the proximal colon of the guinea-pig. ZEITSCHRIFT FUR ZELLFORSCHUNG UND MIKROSKOPISCHE ANATOMIE (VIENNA, AUSTRIA : 1948) 1971; 120:346-63. [PMID: 5153840 DOI: 10.1007/bf00324897] [Citation(s) in RCA: 74] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Bennett T. The adrenergic innervation of the pulmonary vasculature, the lung and the thoracic aorta, and on the presence of aortic bodies in the domestic fowl (Gallus gallus domesticus L.). ZEITSCHRIFT FUR ZELLFORSCHUNG UND MIKROSKOPISCHE ANATOMIE (VIENNA, AUSTRIA : 1948) 1971; 114:117-34. [PMID: 5541838 DOI: 10.1007/bf00339470] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Bennett T. The neuronal and extra-neuronal localisations of biogenic amines in the cervical region of the domestic fowl (Gallus gallus domesticus L.). ZEITSCHRIFT FUR ZELLFORSCHUNG UND MIKROSKOPISCHE ANATOMIE (VIENNA, AUSTRIA : 1948) 1970; 112:443-64. [PMID: 5542332 DOI: 10.1007/bf02584055] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Sato H, Oga A, Nakazato Y. The excitatory and inhibitory innervation of the stomachs of the domestic fowl. JAPANESE JOURNAL OF PHARMACOLOGY 1970; 20:382-97. [PMID: 4395169 DOI: 10.1254/jjp.20.382] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Terence B. Interaction of nerve-medited excitation and inhibition of single smooth muscle cells of the avian gizzard. ACTA ACUST UNITED AC 1970. [DOI: 10.1016/0010-406x(70)90819-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Bennett T, Malmfors T. The adrenergic nervous system of the domestic fowl (Gallus domesticus [L.]). ZEITSCHRIFT FUR ZELLFORSCHUNG UND MIKROSKOPISCHE ANATOMIE (VIENNA, AUSTRIA : 1948) 1970; 106:22-50. [PMID: 5449069 DOI: 10.1007/bf01027715] [Citation(s) in RCA: 121] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Bennett T. The effects of hyoscine and anticholinesterases on cholinergic transmission to the smooth muscle cells of the avian gizzard. Br J Pharmacol 1969; 37:585-94. [PMID: 4310587 PMCID: PMC1703723 DOI: 10.1111/j.1476-5381.1969.tb08497.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
1. Intracellular recordings were made from smooth muscle cells of the pigeon and chick gizzards. Hyoscine (10(-6) g/ml.) blocked, within 2 min, the excitatory junction potentials (E.J.P.s) evoked by transmural stimulation. As the amplitudes of E.J.P.s decreased, their durations also decreased. Hyoscine had no effect on the inhibitory junction potentials (I.J.P.s) evoked by transmural stimulation.2. Initially, physostigmine or neostigmine (10(-7) - 5 x 10(-6) g/ml.) caused a marked increase in the amplitudes of E.J.P.s, without affecting their time courses. Sometimes, anticholinesterases caused a single stimulus to evoke multiple E.J.P.s.3. After several minutes in the presence of high concentrations (10(-6) - 5 x 10(-6) g/ml.) of anticholinesterases the muscle cells were depolarized by about 15-20 mV, and thus the amplitudes of I.J.P.s evoked by transmural stimulation were larger than under control conditions. E.J.P.s summed at much lower stimulation frequencies than normal, an observation which indicated that high concentrations of anticholinesterases increased the durations of the E.J.P.s. Repetitive stimulation evoked a membrane depolarization which persisted for as long as 10 sec after stimulation was stopped.4. These results are discussed in terms of the action of the drugs at the nervesmooth muscle junction and on ganglion cells in the myenteric plexus.
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Bennett T, Cobb JL. Studies on the avian gizzard: the development of the gizzard and its innervation. ZEITSCHRIFT FUR ZELLFORSCHUNG UND MIKROSKOPISCHE ANATOMIE (VIENNA, AUSTRIA : 1948) 1969; 98:599-621. [PMID: 5807130 DOI: 10.1007/bf00347035] [Citation(s) in RCA: 45] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Bennett T, Cobb JL. Studies on the avian gizzard: Auerbach's plexus. ZEITSCHRIFT FUR ZELLFORSCHUNG UND MIKROSKOPISCHE ANATOMIE (VIENNA, AUSTRIA : 1948) 1969; 99:109-20. [PMID: 4897588 DOI: 10.1007/bf00338801] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Bennett T, Cobb JL. Studies on the avian gizzard: morphology and innervation of the smooth muscle. ZEITSCHRIFT FUR ZELLFORSCHUNG UND MIKROSKOPISCHE ANATOMIE (VIENNA, AUSTRIA : 1948) 1969; 96:173-85. [PMID: 5772032 DOI: 10.1007/bf00338765] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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