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FACULTY NEWS
CORRESPONDENCE
533
Changes in the sensitivity of the endplate to depolarizing neuromuscular blocking agents in animals was also reported by Zaimis (1951), Zaimis and Churchill-Davidson (1952), and Thesleff (1955) have shown that, when acetylcholine block is produced in an isolated frog nerve-muscle preparation, after the initial depolarization the end-plate will become repolarized, despite the continued presence of acetylcholine and the persistence of the neuromuscular block. Since the physiological resting state of the endplate is the polarized state, it is conceivable that when it is exposed to the effect of depolarizing drugs like suxamethonium, for prolonged periods, changes might occur in the endplate which make it resistant to depolarizing influences, e.g. acetylcholine. Under such circumstances it is not surprising that the administration of relatively small doses of nondepolarizing neuromuscular blocking agents, which further decrease the sensitivity (increase the resistance) of the endplate to acetylcholine, have an additive effect and cause profound neuromuscular block. The hypothesis here presented is consistent with these experimental findings, and underlines the suggestion that it is the response of the endplate and not the action of the drug which changes.
It is of moment to note here that, similarly, increased sensitivity to small doses (0.75 mg/kg) of gallamine was also observed after the prolonged administration of suxamethonium chloride, and in the same way the administration of decamethonium was found to sensitize patients to both d-tubocurarine and gallamine. The same interrelationship between the depolarizing and nondepolarizing muscle relaxants was observed in dogs (Foldes et al., to be published).
FACULTY NEWS
ROYAL SOCIETY OF MEDICINE, SECTION OF ANAESTHETICS
Brown, D. E. Bourke, T. D. Burtles, R. Conway, C. M. Crampton, C. C. Davies, G. C. Davis, W. S. Deacock, A. R de C. Hill, R. R. W. Howard, J. D. Hughes, D. C. Hurter, D. G. Jowell, D. M. Langdon-Herring, L. Levin, J.
L'Estrange, T. J. Liu, S. Lumsden, J. D. MacPhail, I. Meldrum, W. D. O'Rourke-Brophy, Teresa Rita Rowe, Barbara Mary Skinner, P. A. Topping, Sheila Morgan Verner, I. R. Walsh, R. S. Ward, C. S. Wolfson, B.
F. F. FOLDES,
Mercy Hospital, Pittsburg, Pennsylvania. REFERENCES
Brennan, H. J. (1956). Brit. J. Anaesth., 28, 159. De Pierre. F. (1950). C. R. Acad. Sci. (Paris), 230, 2242. Dripps, R. D. (1953). Ann. Surg., 137, 145. Foldes, F. F., Wnuck, A. L., Hodges, R. J. H., and Beer, E. J. de. (To be published.) Hodges, R. J. H., and Foldes, F. F. (To be published.) Hutter, O. F., and Pascoe, J. E. (1951). Brit. J. Pharmacol., 6, 691. Paton. W. D. M., and Zaimis, E. (1952). Pharmacol. Rev., 4, 219. Thesleff, S. (1955). Nature, 175, 594. Zaimis, E. J. (1951). /. Physiol, 112, 176. Churchill-Davidson, M. C , and Richardson, A. T. (1952). Nature, 170, 617.
REGISTRARS' PRIZE
The Anaesthetic Section of the Royal Society of Medicine is able to offer a Prize of £30 for the best paper submitted by those of Senior Registrar and Registrar status in the National Health Service working in a clinical Anaesthetic Department. Fellowship of the Royal Society of Medicine is not necessary for entry. The subject will be of the author's choice but must be connected with anaesthesia. All papers must be submitted by March 1, 1957. Further details and rules of the Prize can be obtained from the Honorary Secretary, Anaesthetic Section, Royal Society of Medicine, 1 Wimpole Street, London, W.I.
Downloaded from http://bja.oxfordjournals.org/ at University of Arizona on July 6, 2015
IN the final examinations held in July 1956 for the Fellowship in the Faculty of Anaesthetists 76 candidates presented themselves for the examination and 28 were successful. The following were the successful candidates:
R. J. HAMER HODGES,
Portsmouth Group Hospital and Thoracic Surgical Unit, Southampton.
533
Changes in the sensitivity of the endplate to depolarizing neuromuscular blocking agents in animals was also reported by Zaimis (1951), Zaimis and Churchill-Davidson (1952), and Thesleff (1955) have shown that, when acetylcholine block is produced in an isolated frog nerve-muscle preparation, after the initial depolarization the end-plate will become repolarized, despite the continued presence of acetylcholine and the persistence of the neuromuscular block. Since the physiological resting state of the endplate is the polarized state, it is conceivable that when it is exposed to the effect of depolarizing drugs like suxamethonium, for prolonged periods, changes might occur in the endplate which make it resistant to depolarizing influences, e.g. acetylcholine. Under such circumstances it is not surprising that the administration of relatively small doses of nondepolarizing neuromuscular blocking agents, which further decrease the sensitivity (increase the resistance) of the endplate to acetylcholine, have an additive effect and cause profound neuromuscular block. The hypothesis here presented is consistent with these experimental findings, and underlines the suggestion that it is the response of the endplate and not the action of the drug which changes.
It is of moment to note here that, similarly, increased sensitivity to small doses (0.75 mg/kg) of gallamine was also observed after the prolonged administration of suxamethonium chloride, and in the same way the administration of decamethonium was found to sensitize patients to both d-tubocurarine and gallamine. The same interrelationship between the depolarizing and nondepolarizing muscle relaxants was observed in dogs (Foldes et al., to be published).
FACULTY NEWS
ROYAL SOCIETY OF MEDICINE, SECTION OF ANAESTHETICS
Brown, D. E. Bourke, T. D. Burtles, R. Conway, C. M. Crampton, C. C. Davies, G. C. Davis, W. S. Deacock, A. R de C. Hill, R. R. W. Howard, J. D. Hughes, D. C. Hurter, D. G. Jowell, D. M. Langdon-Herring, L. Levin, J.
L'Estrange, T. J. Liu, S. Lumsden, J. D. MacPhail, I. Meldrum, W. D. O'Rourke-Brophy, Teresa Rita Rowe, Barbara Mary Skinner, P. A. Topping, Sheila Morgan Verner, I. R. Walsh, R. S. Ward, C. S. Wolfson, B.
F. F. FOLDES,
Mercy Hospital, Pittsburg, Pennsylvania. REFERENCES
Brennan, H. J. (1956). Brit. J. Anaesth., 28, 159. De Pierre. F. (1950). C. R. Acad. Sci. (Paris), 230, 2242. Dripps, R. D. (1953). Ann. Surg., 137, 145. Foldes, F. F., Wnuck, A. L., Hodges, R. J. H., and Beer, E. J. de. (To be published.) Hodges, R. J. H., and Foldes, F. F. (To be published.) Hutter, O. F., and Pascoe, J. E. (1951). Brit. J. Pharmacol., 6, 691. Paton. W. D. M., and Zaimis, E. (1952). Pharmacol. Rev., 4, 219. Thesleff, S. (1955). Nature, 175, 594. Zaimis, E. J. (1951). /. Physiol, 112, 176. Churchill-Davidson, M. C , and Richardson, A. T. (1952). Nature, 170, 617.
REGISTRARS' PRIZE
The Anaesthetic Section of the Royal Society of Medicine is able to offer a Prize of £30 for the best paper submitted by those of Senior Registrar and Registrar status in the National Health Service working in a clinical Anaesthetic Department. Fellowship of the Royal Society of Medicine is not necessary for entry. The subject will be of the author's choice but must be connected with anaesthesia. All papers must be submitted by March 1, 1957. Further details and rules of the Prize can be obtained from the Honorary Secretary, Anaesthetic Section, Royal Society of Medicine, 1 Wimpole Street, London, W.I.
Downloaded from http://bja.oxfordjournals.org/ at University of Arizona on July 6, 2015
IN the final examinations held in July 1956 for the Fellowship in the Faculty of Anaesthetists 76 candidates presented themselves for the examination and 28 were successful. The following were the successful candidates:
R. J. HAMER HODGES,
Portsmouth Group Hospital and Thoracic Surgical Unit, Southampton.