Beta-endorphin concentration in the femoral and spermatic venous blood of males affected by varicocele.

Several studies in the rat indicate that opioid peptides produced in the testicular interstitial compartment can affect events in the tubular compartment. For example, it is thought that some specific functions of Sertoli cells, such as androgen-binding protein production are decreased by a paracrine mechanism. In this study ACTH beta-endorphin and cortisol were measured in the femoral and spermatic venous blood drawn from 18 patients affected by varicocele during catheterization for venous occlusion. The results showed the absence of a significant secretory gradient of beta-endorphin in the human testis and also demonstrated that this opioid is circulating at picomolar concentrations within human testis under stress conditions.