Acetylcholine Metabolism Research Articles

Choline acetyltransferase in identified neurons of abdominal ganglion of Aplysia californica.

Choline acetyltransferase in identified neurons of abdominal ganglion of Aplysia californica.

The time course of development of acetylcholinesterase and choline acetyltransferase in Drosophila melanogaster.

Twenty stages in the life cycle of Canton-S, a normal strain of Drosophila melanogaster, were investigated for protein content and the activities of choline acetyltransferase and acetylcholinesterase, enzymes associated with the metabolism of acetylcholine. The maximum protein content is reached at the prepupal stage. Specific activities of choline acetyltransferase and acetylcholinesterase were high in the larval stages and again in the mature fly. The activities of these enzymes expressed on a per fly basis were compared with the activities of other enzymes, previously published by other workers, expressed on the same basis. The developmental pattern of acetylcholinesterase and choline acetyltransferase differed from the patterns exhibited by the other enzymes described earlier. It was possible to relate the different enzyme patterns to known changes occurring in the life cycle of Drosophila melanogaster.

Acetylcholine metabolism peculiarities in aging

In experiments on 1, 8–10 and 26–28 months old white rats there were determined: the intensity of acetylcholine formation in isolated atria (Vlk and Tuček, 1964); choline acetylase (EC 2.3.1.6.) activity (Hebb and Waites, 1956; Tuček, 1964) in heart, sciatic nerve and m.gastrocnemius; acetylcholinesterase (EC 3.1.1.7.) and non specific cholinesterase (EC 3.1.1.8.) activity (Vlk and Tuček, 1961) in heart, m.gastrocnemius and intestine. The intentine of acetylcholine formation in isolated atria was decreased with aging. Choline acetylase activity in atria and sciatic nerve was increased at the period of growth but in old rats it was significantly decreased. A considerable drop of choline acetylase activity was found in skeletal muscle of adult rats as compared with 1 month old animals. It remained unchanged in the muscles of old rats. With aging the intensity of acetylcholine hydrolysis decreased in the variuus parts of the heart and skeletal muscle, but did not change in intestine. In atria of old rats, the activity of the non specific cardiac cholinesterase rats was at the same high level as in adults, while in the other parts of heart its activity was gradually decreased with aging. The activity of the skeletal muscles acetylcholinesterase was decreased with aging. Age-conditioned changes in acetylcholine metabolism play an important role in weakening nervous influences upon the tissues and increase their sensitivity to the humoral factors in aging.

Studies on the blocking action of 2-(4-phenyl piperidino) cyclohexanol (AH5183).

1. AH5183 (2-(4-phenyl piperidino) cyclohexanol) produced neuromuscular block of slow onset in rapidly stimulated nerve-skeletal muscle preparations of the rat, chicken and cat.2. The neuromuscular block was not antagonized by neostigmine, tetraethylammonium (TEA) or choline. The rate of onset of transmission failure was enhanced by factors which increase the release of acetylcholine.3. It was concluded that the neuromuscular blocking activity was primarily pre-junctional in origin, being due either to a non-competitive action on the choline transport mechanism, or to an intracellular action on acetylcholine metabolism.4. In high doses AH5183 possessed local anaesthetic activity, but this was considered insufficient to bring about the failure of neuromuscular transmission.5. AH5183 also produced a block of sympathetically innervated preparations that was indistinguishable from that produced by an alpha-adrenoceptor blocking drug.

Biochemical studies on the teratogenic action of Bidrin and other neuroactive agents in developing hen eggs

Bidrin (3-hydroxy- N, N-dimethyl- cis-crotonamide dimethyl phosphate), eserine, and certain other neuroactive agents induce embryonic abnormalities when injected into hen eggs early in development. The effect of Bidrin and other teratogenic and nonteratogenic neuroactive agents on esterase activity, acetylcholine (ACh) levels, and labeled ACh distribution and metabolism within the egg was examined. The inhibition of the activity of acetylcholinesterase and other esterases resulting from injection of Bidrin and other organophosphate esters does not correlate directly with the degree of teratogenesis, and agents that alleviate teratogenesis, such as nicotinamide and nicotinamide adenine dinucleotide, do not significantly alter the magnitude of esterase inhibition. Embryonic levels of ACh do not appear to be related to the degree of teratogenesis, particularly in the presence of an alleviating agent, further indicating that ACh and the cholinergic system do not play a major role in the differentiation processes involved in organophosphate-induced teratogenesis. A permeability barrier appears to be operative between the yolk and the embryo, preventing the transfer of unhydrolyzed ACh but not of its hydrolysis products. Growth abnormalities possibly occur in the presence of certain esterase inhibitors due to nutritional deficiency of the embryo resulting from failure of the embryo to obtain ester hydrolysis products from the yolk.

Cholinergic nerve endings in octopus brain.

Abstract—Optic lobes of the brains of Octopus dofleini werehomogenized hasaline–sucrose medium and subjected to differential and density gradient centrifugation. The fractions and subfractions thus obtained were analysed for acetylcholine (ACh) (bioassay) and protein content and were subjected to electronmicroscopy. Bound ACh was associated with particulate fractions, and a large portion of it could be recovered in subfractions that contained predominantly nerve endings.Expressed in terms of amount of ACh per mg protein, the ACh content of the nerve ending fractions was nearly 100 times greater than that of corresponding fractions previously obtained by others from mammalian brain. Calculations show that this was the minimal amount of ACh to be expected if the isolated nerve endings were predominantly cholinergic. Octopus brain tissue is in therefore very promising for future studies on ACh metabolism and compartmentation cholinergic nerve endings.

Effect of cholinesterase inhibitors on the metabolism of acetylcholine in brain.

Effect of cholinesterase inhibitors on the metabolism of acetylcholine in brain.

The origin of acetylcholine released from guinea-pig intestine and longitudinal muscle strips.

1. Strips of longitudinal muscle can be obtained from guinea-pig ileum either retaining or free from Auerbach's plexus.2. The denervated strip is unresponsive to electrical stimulation by brief shocks, whether given singly or in trains; it also fails to respond to nicotine or dimethylphenylpiperazinium iodide (DMPP), and eserine causes no spasm.3. Denervated strips neither contain detectable acetylcholine (< 0.4 ng/mg), nor release it spontaneously (< 5 pg/mg/min) or in response to stimulation (< 31 pg/mg/min). The acetylcholine metabolism of the innervated strip is therefore that of the adherent Auerbach's plexus. Innervated strips had a mean acetylcholine content of 28 ng/mg, a mean resting output of 94 pg/mg/min and an output in response to stimulation at 10 c/s of 700-1200 pg/mg/min.4. By comparing the responses of innervated and denervated strips it was concluded that arecoline, methylfurmethide, alpha,beta-ethylal-gamma-tri-methylammonium propanediol iodide (2268 F), muscarine, histamine, tremorine, oxytocin, and substance P, like acetylcholine, act primarily on the smooth muscle directly; and that angiotensin, barium, potassium, m-bromophenyl choline ether and 5-hydroxytryptamine have a progressively increasing proportionate effect on the nerve plexus. Nicotine and DMPP were inactive in the absence of the plexus.5. The longitudinal muscle with its accompanying plexus contains about one quarter of the acetylcholine of the whole ileum, and is responsible for about one fifth of the output to electrical stimulation.6. The volley output of acetylcholine by the innervated strip declines sharply as rate of stimulation increases. Output of acetylcholine was reduced by morphine and by cocaine, particularly when resting or when stimulated at low rates.7. Acetylcholine output by whole ileum from guinea-pig declines in the absence of glucose, but is insulin-independent. Output by strips of ileum from rats made diabetic with alloxan was similar to that from normal rats.8. The similarity in properties of acetylcholine output from innervated strips, where it must come from nervous tissue, to that from whole ileum, and the insulin-independence of output from whole ileum suggest that the whole of the acetylcholine output of intestine is nervous in origin.9. Comparison of the acetylcholine metabolism of the innervated strip with that of the superior cervical ganglion suggests that the typical features of the former (high resting output, high volley output at low rates, low minute output at high rates of stimulation, and sensitivity to morphine) may be linked with the absence of specialized neuro-effector junctions and represent a relatively primitive transmission process.

Studies in myasthenia gravis: Part 2. The relation of some clinical and immunological data

The clinical and serological findings in 125 patients with myasthenia gravis are compared. The patients were classified according to their age, sex, type and gravity of their myasthenia and to the presence or absence of a thymoma. The sera of patients and matched controls were studied for the presence of antibodies against skeletal muscle, thymus, thyroid, gastric mucosa, adrenocortex and for the rheumatoid factor, the antinuclear factor and positive LE-cell test and immunoelectrophoretic aberrations. No definite relationship could be established between the clinical condition and the presence of antibodies. However all patients with thymomas had antibodies reacting with skeletal muscle and thymus. They also exceeded the patients without thymomas in the production of antinuclear factor. No influence on the frequency of serological abnormalities could be found according to sex or the duration of the disease; some antibodies and the total antibody production increased with age. Antibodies reacting with muscle were present in nearly 40% of the patients; antibodies reacting with epithelial cells of the thymus were demonstrated in 26%. One or more antibodies occurred in 68% of the patients in contrast to 19% of the controls. Although multiple antibody formation and some clinical traits place myasthenia gravis in the group of idiopathic autoimmune diseases, this provides no causal relationship with the observed defect of acetylcholine metabolism at the neuromuscular junction.

FACTORS INFLUENCING THE ACTION OF MORPHINE ON ACETYLCHOLINE RELEASE IN THE GUINEA‐PIG INTESTINE

British Journal of Pharmacology and ChemotherapyVolume 29, Issue 2 p. 158-167 Free Access FACTORS INFLUENCING THE ACTION OF MORPHINE ON ACETYLCHOLINE RELEASE IN THE GUINEA-PIG INTESTINE I. S. DE LA LANDE, I. S. DE LA LANDE Department of Human Physiology and Pharmacology, University of AdelaideSearch for more papers by this authorR. B. PORTER, R. B. PORTER Department of Human Physiology and Pharmacology, University of Adelaide South Australian Institute of Technology, North Terrace, Adelaide, South Australia.Search for more papers by this author I. S. DE LA LANDE, I. S. DE LA LANDE Department of Human Physiology and Pharmacology, University of AdelaideSearch for more papers by this authorR. B. PORTER, R. B. PORTER Department of Human Physiology and Pharmacology, University of Adelaide South Australian Institute of Technology, North Terrace, Adelaide, South Australia.Search for more papers by this author First published: February 1967 https://doi.org/10.1111/j.1476-5381.1967.tb01949.xCitations: 5 AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat References Ambache, N. (1946). Interaction of drugs and the effect of cooling on the isolated mammalian intestine. J. Physiol. Lond., 104, 266– 287. Ambache, N. (1949). The nicotinic action of substances supposed to be purely smooth muscle stimulating. Effect of BaCl2 and pilocarpine on the superior cervical ganglion. J. Physiol. Lond., 110, 164– 172. Brown, G. L. & Feldberg, W. (1936). The action of potassium on the superior cervical ganglion of the cat. J. Physiol. Lond., 86, 290– 305. Day, MARGARET & Vane, J. R. (1963). An analysis of the direct and indirect actions of drugs on the isolated guinea-pig ileum. Br. J. Pharmac. Chemother., 20, 150– 170. DE LA Lanee, I. S. & Porter, R. B. (1963). The actions of tacrine and amiphenazole on acetylcholine metabolism in the guinea-pig ileum. Aust. J. exp. Biol. med. Sci., 41, 149– 162. Gerhards, K. P., RÖTTCHER, M. & Straub, R. W. (1964a). Wirkungen von Ca and Mg auf Freisetzung und Synthese von Acetylcholin am spontan aktiven Darm. Pflögers Ach. ges. Physiol., 279, 239– 250. Gerhards, K. P., RÖTTCHER, M. & Straub, R. W. (1964b). Wirkungen von Ca and Mg auf Freisetzung und Synthese von Acetylcholin am ruhiggestellten Darm. Ibid., 279, 251– 264. Johnson, E. S. (1963). The origin of the acetylcholine released spontaneously from the guinea-pig isolated ileum. Br. J. Pharmac. Chemother., 21, 555– 568. Harry, J. (1962). Effect of cooling, local anaesthetic compounds and botulinum toxin on the responses of and the acetylcholine output from the electrically transmurally stimulated isolated guinea-pig ileum. Br. J. Pharmac. Chemother., 19, 42– 55. Liley, A. W. (1956). The effects of presynaptic polarization on the spontaneous activity at the mammalian neuromuscular junction. J. Physiol. Lond., 134, 427– 443. Mann, P. J. G., Tennenbaum, M. & Quastel, J. H. (1939), Acetylcholine metabolism in the central nervous system; the effects of potassium and other cations on acetylcholine liberation. Biochem. J., 33, 822– 835. Paton, W. D. M. (1957). The action of morphine and related substances on contraction and on acetylcholine output of coaxially stimulated guinea-pig ileum. Br. J. Pharmac. Chemother., 12, 119– 127. Paton, W. D. M. (1963). Cholinergic transmission and acetylcholine output. Canad. J. Biochem. Physiol, 41, 2637– 2653. Porter, R. B. (1965). Some actions of tacrine on slow muscles of the toad (Bufo marinus) and the chick. Br. J. Pharmac. Chemother., 25, 179– 186. Schaumann, W. (1957). Inhibition by morphine of the release of acetylcholine from the intestine of the guinea-pig. Br. J. Pharmac. Chemother., 12, 115– 118. Citing Literature Volume29, Issue2February 1967Pages 158-167 ReferencesRelatedInformation

Metabolism and significance of acetylcholine in the brain of the adult housefly, Musca domestica L.

Methods are described for the determination of [ 14C] acetylcholine formed in the head tissues of the adult housefly in vivo following [ 14C] acetate injection. Acetylcholine estimated radiometrically and that assayed pharmacologically were in good agreement. This confirms that this ester largely, if not entirely, accounts for the pharmacological activity of head extracts as assayed with the frog rectus abdominis muscle preparation. The data indicated that the acetylcholine content of the brain is due to a steady state of synthesis and hydrolysis with a minimum turnover rate of 6·1 × 10 −5 μmoles acetylcholine/min/head. Turnover was apparently reduced in insects poisoned with acetylcholinesterase inhibitors. These and other observations are interpreted as showing that the ACh system of the brain is highly compartmentalized, synthesis from choline and intracellular acetate being controlled by the availability of choline arising from acetylcholinesterase action. No correlation was found between acetylcholine turnover in vivo and the incidence of light on the compound eye. Turnover was apparently unaffected by surgical elimination of possible nerve activity originating in the thoracic ganglion. It was, apparently, reduced during cyclopropane anaesthesia. Current problems of insect neurophysiology are critically discussed.

Some aspects of the acetylcholine metabolism in the sympathetic ganglion of the irradiated organism

Some aspects of the acetylcholine metabolism in the sympathetic ganglion of the irradiated organism

The effect of reserpine on the acetylcholine release of the cerebral cortex of dog under different anaesthetics.

British Journal of Pharmacology and ChemotherapyVolume 27, Issue 1 p. 131-134 Free Access THE EFFECT OF RESERPINE ON THE ACETYLCHOLINE RELEASE OF THE CEREBRAL CORTEX OF DOG UNDER DIFFERENT ANAESTHETICS C. L. MALHOTRA, C. L. MALHOTRA Department of Pharmacology and Therapeutics, Lady Hardinge Medical College, New Delhi, IndiaSearch for more papers by this authorV. L. MEHTA, V. L. MEHTA Department of Pharmacology and Therapeutics, Lady Hardinge Medical College, New Delhi, IndiaSearch for more papers by this author C. L. MALHOTRA, C. L. MALHOTRA Department of Pharmacology and Therapeutics, Lady Hardinge Medical College, New Delhi, IndiaSearch for more papers by this authorV. L. MEHTA, V. L. MEHTA Department of Pharmacology and Therapeutics, Lady Hardinge Medical College, New Delhi, IndiaSearch for more papers by this author First published: May 1966 https://doi.org/10.1111/j.1476-5381.1966.tb01648.xCitations: 2AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL REFERENCES Anand, B. K. (1952). Influence of temperature on vagal inhibition and liberation of acetylcholine in frog hearts. Am. J. Physiol. (Lond.), 168, 218– 225. Birks, R. T. (1963). Effects of sodium and potassium ions on acetylcholine release. Abstr. 6th Meet Canad. Fed. Biol. Sci., P. 10. Crossland, J. & Merrick, A. J. (1954). The effect of anaesthesia on the acetylcholine content of brain. J. Physiol. (Lond.), 125, 56– 66. Feldberg, W. (1957). Acetylcholine in metabolism of the nervous system. Ed. by D. Richter, pp. 493– 510. London: Pergamon Press. Giarman, N. J. & Pepeu, G. (1962). Drug-induced changes in brain acetylcholine. Br. J. Pharmac. Chemother., 19, 226– 234. Mackintosh, F. C. & Oborin, P. E. (1953). Release of acetylcholine from intact cerebral cortex. Abstr. 19, Int. Physiol. Congr. Montreal, 580. Malhotra, C. L. & Das P. K. (1962). Effect of reserpine on the acetylcholine content of the heart, the ileum and the hypothalamus of the dog. Br. J. Pharmac. Chemother., 18, 190– 193. Malhotra, C. L. & Prasad, K. (1963). The effect of intra (cerebro) ventricular reserpine on the acetylcholine content of the heart, ileum and hypothalamus of the dog. Br. J. Pharmac. Chemother., 21, 355– 360. Malhotra, C. L. & Pundlik, P. G. (1959). The effect of reserpine on the acetylcholine content of different areas of the central nervous system of the dog. Br. J. Pharmac. Chemother., 14, 46– 47. Malhotra, C. L. & Pundlik, P. G. (1965). The effect of some anaesthetics on acetylcholine concentrations of different areas of dog brain. Br. J. Pharmac. Chemother., 24, 348– 351. Mathhews, E. K. & Quilliam, J. P. (1964). Effects of central depressant drugs upon acetylcholine release. Br. J. Pharmac. Chemother., 22, 415– 440. Mitchell, J. F. & Silver, A. (1963). The spontaneous release of acetylcholine from the denervated hemidiaphragm of the rat. J. Physiol. (Lond.), 165, 117– 129. Quastel, D. M. J. & Birks, R. T. (1962). Effects of sodium ion on acetylcholine metabolism in a sympathetic ganglion. Abstr. 5th meet. Canad. Fed. Biol. Sci., P. 64. Richter, D. & Crossland, J. (1949). Variation in acetylcholine content of the brain with physiological state. Am. J. Physiol., 159, 247– 255. Thesleff, S. (1956). The effect of anaesthetic agents on skeletal muscle membrane. Acta physiol. Scand., 37, 335– 349. Citing Literature Volume27, Issue1May 1966Pages 131-134 ReferencesRelatedInformation

The metabolism of acetylcholine in the intact central nervous system of an insect (periplaneta americana l.).

ABSTRACT A very rapid metabolism of 3H-labelled acetylcholine has been demonstrated in the intact abdominal nerve cord. It has been shown that the cholinesterase system is effective in drastically reducing the concentration of acetylcholine in the extracellular fluid of the terminal abdominal ganglion with bathing solutions of up to 10−2 M acetylcholine. Evidence has been obtained which indicates that an appreciable hydrolysis of acetylcholine occurs at the periphery of the nerve cord. This effect is correlated with the electronmicroscopic demonstration of regions of eserine-sensitive cholinesterase located on glial membranes in the periphery of ganglia and connectives. It is suggested that some hydrolysis of extraneous acetylcholine may occur in the fibrous layer of the nerve sheath as a result of an accumulation of diffusible acetylcholinesterase in this region. The results are discussed in relation to the possible involvement of the conven­tional cholinergic system in synaptic transmission in the central nervous system of this insect.

SOME ACTIONS OF TACRINE ON SLOW MUSCLES OF THE TOAD (BUFO MARINUS) AND THE CHICK

British Journal of Pharmacology and ChemotherapyVolume 25, Issue 1 p. 179-186 Free Access SOME ACTIONS OF TACRINE ON SLOW MUSCLES OF THE TOAD (BUFO MARINUS) AND THE CHICK R. B. PORTER, R. B. PORTER Department of Human Physiology and Pharmacology, the University of Adelaide, South Australia Department of Pharmacy, South Australian Institute of Technology, Adelaide, South Australia.Search for more papers by this author R. B. PORTER, R. B. PORTER Department of Human Physiology and Pharmacology, the University of Adelaide, South Australia Department of Pharmacy, South Australian Institute of Technology, Adelaide, South Australia.Search for more papers by this author First published: August 1965 https://doi.org/10.1111/j.1476-5381.1965.tb01770.xCitations: 2 AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat REFERENCES Boyd, H., Chang, V. & Rand, M. J. (1960). The anticholinesterase activity of some antiadrenaline agents. Brit. J. Pharmacol., 15, 525– 531. Burnstock, G., O'Shea, J. & Wood, M. (1963). Comparative physiology of the vertebrate autonomic nervous system. I. Innervation of the urinary bladder of the toad (Bufo Marinus). J. exp. Biol., 40, 403– 419. Child, K. J. & Zaimis, E. (1960). A new biological method for the assay of depolarising substances using the isolated semispinalis muscle of the chick. Brit. J. Pharmacol., 15, 412– 416. de la Lande, I. S. & Porter, R. B. (1963). The actions of tacrine and amiphenazole on acetylcholine metabolism in the guinea pig ileum. Aust. J. exp. Biol. med. Sci., 41, 149– 162. Gershon, S. & Shaw, F. H. (1958). Tetrahydroaminacrin as a decurarising agent. J. Pharm. Pharmacol., 10, 638– 641. Hawkins, R. D. & Mendel, B. (1946). True cholinesterases with pronounced resistance to eserine. J. cell, comp. Physiol., 27, 69– 85. Hobbiger, F. (1950). The action of carbamic esters and tetraethyl pyrophosphate on normal and curarised frog rectus muscle. Brit. J. Pharmacol., 4, 37– 48. Kirschner, L. B. & Stone, W. E. (1950). The action of inhibitors at the myoneural junction. J. gen. Physiol., 34, 821– 834. McCaul, K. & Robinson, G. D. (1962). Suxamethonium “extension” by tetrahydroaminacrine. Brit. J. Anaesth., 34, 536– 542. Quilliam, J. P. & Strong, F. G. (1949). Some observations upon the pharmacological activity of DFP. Brit. J. Pharmacol., 4, 168– 176. Shaw, F. H. & Bentley, G. A. (1953). The pharmacology of some new anticholinesterases. Aust. J. exp. Biol. med. Sci., 31, 573– 576. Shaw, F. H. & Bentley, G. A. (1955). Morphine antagonism. Aust. J. exp. Biol. med. Sci., 33, 143– 152. Stone, V., Moon, W. & Shaw, F. H. (1961). The treatment of intractable pain with morphine and tetrahydroaminacrine. Brit. med. J., i, 471– 473. Tyler, C. (1960). The assay of acetylcholine with the isolated semispinalis cervicis muscle of the chick. Analyst, 85, 8– 11. Citing Literature Volume25, Issue1August 1965Pages 179-186 ReferencesRelatedInformation

Appearance of biochemical components related to acetylcholine metabolism during the embryonic development of chick brain

The normal pattern of appearance of acetylcholinesterase, acetylcholine, choline acetylase, acetothiokinase and choline during the development of chick embryo brain has been determined. During the early period of development, no dramatic changes occur in the concentration of these components of the acetylcholine metabolizing system. During the period from 13 days to hatching, when nervous function is initiated in the major portions of the chick brain, marked increases occur in the concentrations of acetylcholinesterase, choline acetylase, choline and protein and the acetylcholine concentration increases slightly. The concentration of acetothiokinase remains constant throughout the course of embryonic development. The possible interrelations of these changes are discussed.

CENTRALLY ACTIVE DRUGS AND TRANSMISSION THROUGH THE ISOLATED SUPERIOR CERVICAL GANGLION PREPARATION OF THE RABBIT WHEN STIMULATED REPETITIVELY.

British Journal of Pharmacology and ChemotherapyVolume 24, Issue 1 p. 76-88 Free Access CENTRALLY ACTIVE DRUGS AND TRANSMISSION THROUGH THE ISOLATED SUPERIOR CERVICAL GANGLION PREPARATION OF THE RABBIT WHEN STIMULATED REPETITIVELY R. C. ELLIOTT, R. C. ELLIOTT Department of Pharmacology, Medical College of St. Bartholomew's Hospital, London, E.C.1Search for more papers by this author R. C. ELLIOTT, R. C. ELLIOTT Department of Pharmacology, Medical College of St. Bartholomew's Hospital, London, E.C.1Search for more papers by this author First published: February 1965 https://doi.org/10.1111/j.1476-5381.1965.tb02081.xCitations: 7AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL REFERENCES Birks, R. & MacIntosh, F. C. (1961). Acetylcholine metabolism of a sympathetic ganglion. Canad. J. Biochem., 39, 787– 827. Bell, P. M. G. (1962). A unit form of construction of electrical apparatus. J. Physiol. (Lond.), 161, 6– 7P. Brown, D. A. & Quilliam, J. P. (1964). The effects of some centrally-acting drugs on ganglionic transmission in the cat. Brit. J. Pharmacol., 23, 241– 256. Bülbring, E. (1944). The action of adrenaline on transmission in the superior cervical ganglion. J. Physiol. (Lond.), 103, 55– 67. Eccles, R. M. & Libet, B. (1961). Origin and blockade of the synaptic responses of curarized sympathetic ganglia. J. Physiol. (Lond.), 157, 484– 503. Elliott, R. C. (1963). Centrally-active Drugs and Ganglionic Transmission. Ph.D. thesis at the University of London. Elliott, R. C. & Quilliam, J. P. (1964). Some actions of centrally active and other drugs on the transmission of single nerve impulses through the isolated superior cervical ganglion preparation of the rabbit. Brit. J. Pharmacol., 23, 222– 240. Exley, K. A. (1954). Depression of autonomic ganglia by barbiturates. Brit. J. Pharmacol., 9, 170– 181. Folkow, B. (1952). Impulse frequency in sympathetic vasomotor fibres correlated to the release and elimination of the transmitter. Acta physiol. scand., 25, 49– 76. Marley, E. & Paton, W. D. M. (1959). Pharmacology of methylpentynol and methylpentynol carbamate. Brit. J. Pharmacol., 14, 303– 306. Marrazzi, A. S. (1939). Adrenergic inhibition at sympathetic synapses. Amer. J. Physiol., 127, 738– 744. Marrazzi, A. S. & Marrazzi, R. N. (1947). Further localization and analysis of adrenergic synaptic inhibition. J. Neurophysiol., 10, 165– 178. Matthews, R. J. (1956). The effect of epinephrine, levarterenol and dl-isoproterenol on transmission in the superior cervical ganglion of the cat. J. Pharmacol. exp. Ther., 116, 433– 443. Matthews, E. K. & Quilliam, J. P. (1964). Effects of central depressant drugs upon acetylcholine release. Brit. J. Pharmacol., 22, 415– 440. Pardo, E. G., Cato, J., Gijón, E. & Florida, F. Alonso-de (1963). Influence of several adrenergic drugs on synaptic transmission through the superior cervical and the ciliary ganglia of the cat. J. Pharmacol. exp. Ther., 139, 296– 303. Paton, W. D. M. & Thompson, J. W. (1953). The mechanism of action of adrenaline on the superior cervical ganglion of the cat. Abst. XIX Int. Physiol. Congr., p. 664. Paton, W. D. M. & Zaimis, E. J. (1951). Paralysis of autonomic ganglia by methonium salts. Brit. J. Pharmacol., 6, 155– 168. Reinert, H. (1963). Role of origin of noradrenaline in the superior cervical ganglion. J. Physiol. (Lond.). 167, 18– 29. Citing Literature Volume24, Issue1February 1965Pages 76-88 ReferencesRelatedInformation

The influence of certain cholinergic substances on accommodation in a nerve trunk

Drugs (2-methylnaphthaquinone, atropine, and eserine) which alter the metabolism and action of acetylcholine cause specific changes in the rate of accommodation of the frog sciatic nerve, changes which vary in their extent and in their direction. The results obtained confirm the opinion we expressed previously that acetylcholine is concerned in the changes occurring in nervous tissue during accommodation.

Alteration of acetylicholinesterase in the cochlea.

In an attempt to clarify the aspect of the acetylcholine (Ach) metabolism occurring within the cochlea of the guinea-pig, determinations of aeetylcholin-esterase (ChE) activity within it have been made, and the alteration of ChE under pathological conditions was studied. The animals were exposed to sounds or were given D.H.S.M. and D.F.P. systemically. The ChE activity was quantitatively determined with use of Cartesian diver respirometer. By the freezing and melting procedures, the ChE activity was expressed in terms of “functional and reserve ChE.” The following results were obtained: 1) In normal specimens, ChE activity per mm in the lower coil was greater than in the upper coil, but by the freezing and melting procedure, its activity increased in both coils within a similar range. 2) In the tissues of the sound-exposed animals, functional ChE diminished in the lower coil, while reserve ChE in the upper coil diminished. 3) In the tissues of the D.F.P.-injected animals, both functional and reserve ChE slightly diminished in the both coils. 4) In the tissues of the D.H.S.M.-injected animals, considerable individual differences of ChE were characteristic, though both types of ChE decreased on the average. 5) ChE in the cochlea showed a tendency to change its activity characteristic-ally under each above-mentioned pathological condition.

The effect of disturbance of acetylcholine metabolism on cathode threshold parabiosis curves and on the functional stability of the nerve trunk

In disturbance of acetylcholine synthesis caused by preliminary excision of the pancreas or by treating the nerve with 2-methylnaphthoquinone (a cholinesterase inhibitor) there is an accelerated development of nerve parabiosis under the effect of direct current cathode. The minimal intensity of direct current, maintaining a nonconductivity state, decreases in these conditions more rapidly and reaches lower values than in cases of control preparations. As a result of this the curve of threshold cathodic parabiosis proves to be displaced to the axis of ordinates and to the axis of abscissae. The occuring changes testify to a reduction of the nerve resistance to the action of alteration and decrease of restorative, compensatory processes.