Korchynska L. Effect of organophosphorus insecticides on dynamic charactristics of the frog muscle fiber contraction.

The investigation of the influence of organophosphorus insecticides such as pirimiphosmethyl, diazinon and chlorpyrifos on the contraction dynamics of skeletal muscle fibers of frog Rana Temporaria is described at this work. The research was carried out using tensometry, differential centrifugation and spectrophotometry. The experiments were carried out in the isotonic regime under the constant control of dynamic parameters of the contraction. During the experiments the strength of contraction, the change of the length, the ambient solution temperature and the stimulation signal parameters were fixed. The characteristic curves of dynamic parameters of the skeletal muscle contraction in the dependent of insecticides concentration were obtained. The changes of muscle contraction dynamic parameters during pretetanic and tetanic stages of contraction were investigated. The decrease of strength and muscle lendth change during frog skeletal muscle contraction in results of noncholinergic effects of organophosphorus insecticides was showed.