STUDIES ON THE PERISTALTIC MOVEMENTS OF RAT SEMINIFEROUS TUBULES BY MICROPUNCTURE METHOD

Abstract

Since Roosen-Runge recorded contractile activity cinematographically in seminiferous tubules of rats and dogs, a considerable volume of work has been carried out on the anatomy of smooth muscle-like cells, namely, myoid cells that are responsible for the contractile movements of the seminiferous tubules. However, the regulation of these contractile movements still remains unclear. Therefore, in order to prove its contractility, it was attempted to photograph the change of its wall on injection of 0.5% Sudan black solution into an isolated rat seminiferous tubule. Furthermore, the responses of the rat seminiferous tubules to autonomic drugs and to stimulation of the perivascular nerve running along the spermatic vessels were examined by recording the intratubular pressure with a servo-null pressure measuring device. The dose-dependent responses of the rat seminiferous tubule to acetylcholine and noradrenaline were demonstrated. The contraction of the seminiferous tubules was elicited by penvascular nerve stimulation with A. C. (50Hz, 3V, 5sec). From the results of the responses to autonomic drugs and to perivascular nerve stimulation in the presence of various blockers, it was concluded that there were adrenergic α-, β-receptors and muscarinic receptors in the myoid cell of rat seminiferous tubule and that the contractions of seminiferous tubules were regulated by adrenergic nerve fibers.
For histological investigations of the innervation of the myoid cells an indirect immunostaining technique, a silver impregnation technique and an electron microscopic study of nerve endings in seminiferous tubule walls after administration of 5-Hydroxydopamine and L-DOPA, ‘false adrenergic neurotransmitters’ as markers of adrenergic nerve elements were used. The staining of the myoid cells with actin antibody to highly purified actin from Physarum as an antigen was performed. The nerve fibers close to the myoid cells were shown using the indirect immunoperoxidase and the Gros-Schultze's silver impregnation technique. Electron microscopic study using false adrenergic neurotransmitters revealed a nerve terminal partly surrounded by a Schwann cell containing the dense-cored synaptic vesicles between fibrocyte and myoid cell.