[beta-Endorphins and the male reproductive system]

In the antique Chinese culture, it was already known about opioide for therapeutic usage. On 1975, Hughes et al., identificated two endogen pentapetides with potent opiate activity Leu-enkephalin and Met-enkephalin, ever since beta-Endorphin have been considered involucrated in many biological functions. beta-Endorphin have found in testis, seminal vesicle and prostate in different species. It has been observed a paracrine effect between in Leydig and Sertoli cells and inhibit the basal release of LH in man by inhibiting its pulsatile discharge. In this paper is discussed, in a general way, localization and production sites of beta-Endorphin especially their participation in male reproductive tract-physiology. Finally, it is mentioned the experimental methodology to identify and quantify beta-Endorphin in blood plasma and semen.