The influence of bromocriptine on sexual activity in ethanol-exposed male rats.

Long-lasting intake of ethanol and its influence on certain changes in the activity of male sexual hormones is the subject of numerous experiments. It is suggested that the decreased libido, hypotrophy of testicles and impotence in individuals subjected to ethanol, are connected with the lowered level of testosterone. Various mechanisms may be responsible for such an activity of ethanol. There has been pointed out that long-lasting intake of ethanol quickens the metabolism of testosterone in the liver. The results of other experiments indicate that ethanol and/or its metabolite, acetaldehyde decrease the biosynthesis of testosterone in the Leydig cells. It has been proved, too, that ethanol reduces the number of testicular gonadotropin receptors what, additionally, decreases the synthesis of testosterone. Another reason for the disordered function of gonads in alcoholics may be the influence of ethanol on the central nervous system structures. Particularly, it refers to the neurones of hypothalamus because they can regulate excretion of the hormones of anterior pituitary gland. In this way, hypothalamus may affect not only the level of the hormones produced by gonades but also to release pituitary prolactin. The present state of research indicates that ethanol results in clear changes in the function of the dopaminergic system of the brain. The influence of ethanol upon the neurones of this system depends on its dose and the period of activity. Most researches point out that prolonged administration of ethanol leads to hypofunction of dopaminergic neurones of the brain.