The effect of protein sensitization on the contractile function of isolated fast mice muscle is determined by postsynaptic membrane condition

The mechanisms of organism allergic reorganization on the contractile function of the isolated «fast» skeletal muscle of mice leg - extensor digitorum longus, have been studied. It has been demonstrated that in case of protein sensitization the contractile force of fast muscle produced by cholinoceptive carbacholine decreases. It has been also found that protein sensitization results in the decrease of acetylcholine non-quant secretion in the muscle fiber end-plate zone of fast skeletal muscle. The vector of contractile force change of skeletal muscle under cholinomimetic influence for protein sensitization correlates with the change in acetylcholine non-quantal secretion. It has been suggested, that the mechanisms of the change in fast skeletal muscle contractile function for protein sensitization are first of all caused by the dynamics of cholinomediated processes of membrane excitation in skeletal muscle fibers.