ABSTRACT
The Renin-Angiotensin System has been shown to affect the female and male reproductive systems of many different species including the human, rat, and bovine. A significant increase in angiotensin-converting enzyme (ACE) activity with increased age was reported in all segments of the male reproductive tract studied. The ACE present in the seminal fluid could possibly function to convert the relatively inactive Angiotensin (Ang I) to the potent Ang II in the female reproductive tract after ejaculation. Male rats caged with female rats for two weeks also showed a significant increase in ACE activity in the testis, efferent ducts and caput epididymis. The prostate is also known to contain ACE that has been localized to the endothelial cells of the vessels of the rat. The concentration of ACE present in the seminal plasma of the epididymis has also been reported to correlate directly with the quality of semen.
