Evidence for blood myo-inositol as a source of the epididymal secretion in the perfused cauda epididymidis of the rat.

Abstract

The movement of radioactive inositol and glucose across the epididymal epithelium have been studied by perfusion of fluid, which has the major electrolyte compositions resemble those in the native epididymal fluid, through the lumen of a sperm free tubule of the distal cauda epididymidis of intact and nephrectomized rats. During intravenous infusion of (3H)-myo-inositol into the intact rats, labelled myo-inositol and its metabolites entered the lumen. However, only labelled inositol was found in the luminal perfusate when radioactive inositol was infused into the nephrectomized rat. On the other hand, after infusion of (14C)-glucose no trace of labelled inositol appeared in the lumen. Instead, the luminal radioactivity could be accounted for by labelled glucose. The results indicate that the myo-inositol present in the luminal fluid of the rat cauda epididymidis originates, in part, from blood inositol and, in part, from blood glucose.