Effect of glucose on uptake of l-lysine-H3 in cells of the seminiferous epithelium

Abstract

The incorporation of L-lysine-H3 into protein of cells of the seminiferous epithelium of the rat has been studied radioautographically following incubation of slices of testis with the labeled precursor for 1 hr. In addition, the effect of exogenous glucose on protein labeling of the successive cells of the cycle of the seminiferous epithelium of the rat has been investigated. In the absence of added glucose the most heavily labeled cells of the seminiferous epithelium were the resting primary spermatocytes, with little or no label appearing in the remaining cells of the spermatogenic cycle. The addition of glucose caused a significant increase in protein labeling from tritiated lysine in all the cells of the spermatogenic cycle with the greatest degree of stimulation being noted in the pachytene primary spermatocytes and spermatids. It is suggested that the transition from somatic mitosis to the 1st meiotic prophase is associated with a marked increase in protein labeling, and that the incorporation of radioactive lysine into protein of the pachytene primary spermatocytes and spermatids is the most sensitive to the addition of exogenous glucose.