Presynaptic function modified by acetylcholine-receptor interaction in experimental autoimmune myasthenia gravis.

M Takamori; S Sakato; S Okumura

doi:10.1016/0022-510x(84)90013-3

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Presynaptic function modified by acetylcholine-receptor interaction in experimental autoimmune myasthenia gravis.

M Takamori·S Sakato·S Okumura

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Abstract

Rats with experimental autoimmune myasthenia gravis (EAMG) were studied to test if the postsynaptic receptor disease would be modified by a compensating presynaptic effect of acetylcholine (ACh) being mediated through the presynaptic receptor. In normal rat phrenic-diaphragms, the ACh quantum content was estimated using the cut-muscle technique by which the evoked release of transmitter can be measured in the absence of blocking agents; values were significantly increased when the ACh receptor was blocked by d-tubocurarine. In rats with EAMG, this presynaptic autoregulation acted to compensate the postsynaptic failure, but did not reach the range of d-tubocurarine-treated controls. Results may be explained by either the difference between the receptor sites for myasthenic antibodies and d-tubocurarine or the immunological property of the presynaptic receptor which may differ from the postsynaptic one.

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Acetylcholine Animals Autoimmune Diseases Diaphragm Female Membrane Potentials Motor Endplate Motor Neurons Myasthenia Gravis Neuromuscular Junction Phrenic Nerve Rats Rats, Inbred Lew Receptors, Cholinergic Synapses Synaptic Transmission Tubocurarine Journal Article Research Support, Non-U.S. Gov't

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M Takamori, S Sakato, S Okumura. Presynaptic function modified by acetylcholine-receptor interaction in experimental autoimmune myasthenia gravis.. https://doi.org/10.1016/0022-510x(84)90013-3

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