Changes in the lability of smooth muscle during stimulation of the sympathetic and parasympathetic nerves

Summary The effect of sympathetic and parasympathetic nerves of a smooth muscle—the retractor penis—was investigated. Stimulation of the sympathetic nerve extends the limits of the optimal and pessimal frequency of stimulation towards greater frequencies, the action current frequency and amplitude increase, while the value of the resting current decreases.On stimulation of the parasympathetic nerve, the action current frequencies become decreased, their amplitude declines and the resting current rises.A suggestion is made that the antagonism of the sympathetic and parasympathetic innervation of the smooth muscle apparently is due to the action exerted on the functional properties of the muscle, particularly on its lability.(Presented by Active Member AMN SSSR V. V. Parin) Translated from Byulleten' éksperimental'noi biologii i meditsiny Vol. 49, No. 2, pp. 22–26, February, 1960.