Mitotic activity during muscular exertion

Summary

Brief muscular exertions in mice lead to a marked reduction of mitotic activity in the corneal epithelium associated with the delay in the onset of mitosis. In adrenalectomized animals cellular mitosis is inhibited later than in control animals. The perfusion fluid passing through the vessels of the strained muscle inhibits the cleavage of frog eggs. The deceleration of the cleavage rate is connected mainly with the prolongation of interkinesis. The action of metabolites of the working muscle is nonspecific. At least two factors are involved in the reduction of mitotic activity during physical exertion: initial reduction of mitotic activity is caused by intensified adrenalin secretion, whereas subsequent inhibition of mitoses is induced by the metabolites of the working muscle.