Summary
By utilizing high frequency nerve stimulation, we observed the effects of morphine sulphate, 0.5 mg kg-1 on human neuromuscular transmission. Tetanic fade at 50, 100 and 200 hz did not change during the one hour period after infusion of morphine. Post-tetanic depression (PTD) of single twitch response increased progressively with time over the one-hour study period. This was most marked with the 100 and 200 hz tetanic frequencies. In contrast, control subjects displayed either no change, or a slight increase (post-tetanic facilitation; PTF), over a similar one-hour test period. We believe these results are best explained by a presynaptic action of morphine, whereby intraterminal mobilization of acetylcholine is impaired by the opiate narcotic drug.
Résumé
A ľaide de stimulus nerveux à fréquences élevées, nous avons étudié les effets ďune dose de 0.5 mgkg-1 de sulfate de morphine sur la transmission neuromusculaire de ľhomme. Ľépuisement tétanique à 50, 100 et 200 Hz n’a pas changé dans ľheure qui a suivi ľinjection de morphine. Dans la même période, nous avons observé que la diminution de la réponse à un stimulus unique après tétanisation devenait plus marquée avec le passage du temps; le phénomène était plus intense avec des fréquences de 100 et 200 Hz.
D’autre part, on n’a pas observé de changements ou, tout au plus, a-t-on noté une légère augmentation de la facilitation post-tétanique chez les sujets contrôles.
Nous croyons que ces résultats seraient explicables par une activité présynaptique de la morphine, qui gênerait la mobilisation de ľacétylcholine aux terminus nerveux.
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References
Bellville, J.W., Cohen, E.N., &Hamilton, J. The interaction of morphine and d-tubocurarine on respiration and grip strength in man. Clin. Pharmacol. & Therap.5: 35 (1963).
Paton, W.D.M. The action of morphine and related substances on contraction and an acetylcholine output of coaxially stimulated guinea-pig ileum. Brit. J. Pharmacol.12: 119 (1957).
Cox, B.M. &Weinstock, M. The effect of analgesic drugs on the release of acetylcholine from electrically stimulated guinea-pig ileum. Br. J. Pharmac. Chemother.27: 81 (1966).
Gyang, E.A. &Kosterlitz, H.W. Agonist and antagonist action of morphine-like drugs on the guinea-pig isolated ileum. Br. J. Pharmac. Chemother.27: 514 (1966).
Frederickson, R.C.A. &Pinsky. C. Morphine and nalorphine impair neuromuscular transmission. Nature New Biol.231: 94 (1971).
Pinsky, C. &Frederickson, R.C.A. Morphine impairs acetylcholine release but facilitates acetylcholine action at a skeletal neuromuscular junction. Nature New Biol.231: 93 (1971).
Soteropoulos, G.C. &Standaert, F.G. Neuromuscular effect of morphine and naloxone. J. of Pharmacol. & Exp. Therap.184: 136 (1973).
Slomić, A., Rosenfalck, A., &Buchthal, F. Electrical and mechanical responses of normal and myasthenic muscle. Brain Research10: 1 (1968).
Epstein, R.A. &Epstein, R.M. The electromyogram and the technical response of indirectly stimulated muscle in anesthetized man following curarization. Anesthesiology38: 212 (1973).
Frederickson, R.C.A. Actions of morphine on cholinergic transmission — importance in opiate narcotic dependence. Ph.D. Thesis, University of Manitoba (1972).
Bell, K.M. &Reese, J.M.H. The depressant action of morphine on transmission at a skeletal neuromuscular junction is non-specific. J. Pharm. Pharmac.26: 686 (1974).
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Duke, P.C., Johns, C.H., Pinsky, C. et al. The effect of morphine on human neuromuscular transmission. Canad. Anaesth. Soc. J. 26, 201–205 (1979). https://doi.org/10.1007/BF03006982
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DOI: https://doi.org/10.1007/BF03006982