Hormonal status of male reproductive system: androgens and estrogens in the testis and epididymis. In vivo and in vitro approaches.

This article investigates the role of androgens and estrogens, particularly testosterone, in the male reproductive system, focusing on the human, rodent and equine testes and epididymides, under both normal and pathological conditions. It also explores how hormone levels, altered gene expressions, and changes in enzymatic activity affect male reproductive function.

Androgens and Estrogens in Male Reproductive System

• The authors summarize their findings on the functioning of androgens and estrogens in the testes and epididymides. These are two critical components of the male reproductive system in humans, rodents, and equines.
• The main focus is on testosterone, an androgen produced by Leydig cells in the testes, which is the dominant androgen in circulation in men and adult male mammals. This hormone, along with its metabolites, forms a significant proportion of the total circulating steroids in these species.

Metabolism and Action of Androgens

• The study highlights that androgen metabolism can amplify the effect of testosterone by transforming it into dihydrotestosterone (DHT) or estradiol through a process called aromatization.
• The distribution of androgen and estrogen receptors (ARs and ERs) in male reproductive tissues is significant because these receptors mediate the action of androgens and estrogens.

Role of Aromatase, ERs, and DHT in Hormonal Regulation

• The authors discuss the role of the enzyme aromatase and ERs in controlling the action of estrogens in males.
• The importance of DHT in the hormonal regulation of the epididymis, a tube that connects the testes to the vas deferens, is also discussed.
• The study examines changes in the epididymis caused by finasteride treatment and lead-induced oxidative stress.

Male Reproductive Function Reflected by Alterations

• The researchers also look at how changes in enzymatic activity, differences in steroid hormone levels, the distribution of steroid hormone receptors, and altered expression of genes related to antioxidant enzymes all reflect the male reproductive function of the testis and epididymis.