Abstract
Isometric tension developed by rat soleus and extensor digitorum longus (EDL) muscles in response to acetylcholine (Ach) applied in vitro was recorded. Tension of contractures elicited in response to Ach increased after muscles had been incubated with phospholipase C, pepsin, or soluble fractions prepared from muscle homogenate.
Using intracellular microelectrodes, resting membrane potential (RMP) and depolarisation in response to Ach added to the bathing medium were recorded in endplate-free regions of the muscle fibres. No significant change in RMP was observed in muscles incubated with soluble muscle fraction or phospholipase C, but depolarisation in response to Ach or carbachol was significantly increased. The time course for the increase in depolarisation and the contracture response to Ach was similar.
When all available receptors were blocked with α-bungarotoxin prior to incubation so that no response to Ach could be elicited, with subsequent incubation in muscle soluble fraction or phospholipase C, both contractures and depolarisation in response to Ach returned. These results support the hypothesis that receptors, not previously available to interact with Ach or α-bungarotoxin were revealed following incubation.
Similar content being viewed by others
References
Axelsson, J., Thesleff, S.: A study of supersensitivity in denervated mammalian skeletal muscle. J. Physiol. (Lond.)147, 178–193 (1959)
Betz, W., Sakmann, B.: Effect of proteolytic enzymes on structure and function of frog neuromuscular junctions. J. Physiol. (Lond.)230, 673–688 (1973)
Blunt, R., Jones, R., Vrbová, G.: Inhibition of cell division and the development of denervation hypersensitivity in skeletal muscle. Pflügers Arch.355, 189–204 (1975)
Brockes, J. P., Hall, Z. W.: Synthesis of acetylcholine receptor by denervated rat diaphragm muscle. Proc. Natl. Acad. Sci. USA72, 1368–1372 (1975)
Brown, G. L.: The actions of acetylcholine on denervated mammalian and frog's muscle. J. Physiol. (Lond.)87, 438–461 (1937)
Bunch, W., Kallsen, G., Berry, J., Edwards, C.: The effect of denervation on the incorporation of32p and [3H]glycerol by the muscle membrane. J. Neurochem.17, 613–620 (1970)
Devreotes, P. N., Fambrough, D. M.: Acetylcholine receptor turnover in membranes of developing muscle fibers. J. Cell Biol.65, 335–358 (1975)
Durrel, J., Garland, J. T., Friedel, R. O.: Acetylcholine action: Biochemical aspects. Science165, 826–866 (1969)
Elmqvist, D., Thesleff, S.: A study of acetylcholine — induced contractures in denervated mammalian muscle. Acta Pharmacol. Toxicol.17, 84–93 (1960)
Fambrough, D. M.: Acetylcholine sensitivity of muscle fibre membranes: mechanism of regulation by motoneurones. Science168, 372–373 (1970)
Fatt, P., Katz, B.: An analysis of the endplate potential recorded with an intracellular electrode. J. Physiol. (Lond.)115, 2320–2370 (1951)
Gordon, A. S., Davies, C. G., Milfay, D., Diamond, I.: Phosphorylation of acetylcholine receptor by endogenous membrane protein kinase in receptor enriched membranes ofTorpedo california. Nature267, 359–540 (1977)
Grampp, W., Harris, J. B., Thesleff, S.: Inhibition of denervation changes in skeletal muscle by blockers of protein synthesis. J. Physiol. (Lond.)221, 743–754 (1972)
Ikezawa, H., Yamanegi, M., Taguchi, R., Miyashita, T., Ohyabu, T.: Studies on phosphatidylinositol phosphodiesterase (phospholipase C type) of Bacillus cereus. Biochem. Biophys. Acta450, 154–164 (1976)
Katz, B., Miledi, R.: Further observations on the distribution of acetylcholine-reactive sites in skeletal muscle. J. Physiol. (Lond.)170, 379–388 (1964)
Lavoie, P.-A., Collier, B., Tenenhouse, A.: Comparison of α-bungarotoxin binding to skeletal muscles after inactivity or denervation. Nature260, 349–350 (1976)
Low, M. G., Finean, J. B.: Non-lytic release of acetylcholinesterase from erythrocytes by a phosphatidylinositol specific phospholipase C. FEBS Letters82, 143–146 (1977)
Lunt, G. G., Stefani, R., De Robertis, E.: Increased incorporation of [G-3H]lencine into a possible ‘receptor’ proteolipid in denervated muscle in vivo. J. Neurochem.18, 1545–1553 (1971)
Miledi, R.: Junctional and extrajunctional acetylcholine receptors in skeletal muscle fibres. J. Physiol. (Lond.)151, 24–30 (1960)
Miledi, R., Potter, L. T.: Acetylcholine receptors in muscle fibres. Nature233, 599–603 (1971)
Pestronk, A., Drachmann, D. B., Griffin, J. W.: Effect of muscle disuse on acetylcholine receptors. Nature260, 352–353 (1976)
Porter, C. W., Chiu, T. H., Weickowski, J., Barnard, E. A.: Types and locations of cholinergic receptor-like molecules in muscle fibres. Nature New Biol.241, 3–7 (1973)
de Robertis, E.: Central and peripheral cholinergic receptor protein. Isolation and molecular properties. In: Neurochemistry of cholinergic recepors, pp. 63–84 (de Robertis, E., Schact, J., eds.). New York: Raven Press 1974
Slein, W. M., Logan, G. F.: Characterisation of the phospholipases of Bacillus cereus and their effects on erythrocytes, bone and kidney cells. J. Bacteriol.90, 61–81 (1965)
Teichberg, V. I., Sobel, A., Changeux, J. P.: In vitro phosphorylation of the acetylcholine receptor. Nature267, 540–542 (1977)
Thesleff, S.: The mode of neuromuscular block caused by acetylcholine, nicotine, decamethonium and succinylcholine. Acta Physiol. Scand.34, 218–231 (1955)
Watson, J. E., Gordon, T., Jones, R., Smith, M. E.: The effect of muscle extracts on the contracture response of skeletal muscle to acetylcholine. Pfügers Arch.363, 161–166 (1976)
Weichselbaum, T. E.: An accurate and rapid method for the determination of proteins in small amounts of blood, serum and plasma. Am. J. Clin. Path.16, Techn. sect.40, 40–49 (1946)
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Harborne, A.J., Smith, M.E. & Jones, R. The effect of hydrolytic enzymes on the acetylcholine sensitivity of the skeletal muscle cell membrane. Pflugers Arch. 377, 147–153 (1978). https://doi.org/10.1007/BF00582845
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00582845