The effect of exogenous acetylcholine on the effectiveness of neuromuscular transmission in rat diaphragm fatigue
Kubasov, I.V.; Krivoĭ, I.I.; Lopatina, E.V.
Biulleten' Eksperimental'noi Biologii i Meditsiny 118(11): 457-459
1994
ISSN/ISBN: 0365-9615 PMID: 7888638 Document Number: 431401
Phrenic diaphragmatic preparations of rats with armin-inhibited acetylcholinesterase were fatigued by infrequent nerve stimulation. Increased amplitudes of isometric contractions of continuously fatigued muscles and amplitudes of total muscle action potentials were observed during 1-2 hours after acetylcholine (10-7 M) was added to the solution for 15 min. Contractions in response to direct muscle stimulation did not change. Membrane rest potential of muscle fibers deviated to hyperpolarization and retained this state during 2 hours after acetylcholine removal from the solution.