Effects of mepartricin on estradiol and testosterone serum levels and on prostatic estrogen, androgen and adrenergic receptor concentrations in adultrats

The effects induced by oral administration of 0, 5 and 20 mg of meparticin kg(-1) of body weight for 28 days (group 1, 2 and 3, respectively) upon pro static estrogen, androgen, alpha (1)- and beta -adrenergic receptor concent rations and on estradiol and testosterone serum levels in adult male rats w ere studied. The effects produced by mepartricin treatments on the weight a nd dimension of the gland were investigated. Both mepartricin dosages induc ed significant decreases (P < 0.05) of the absolute and relative weights an d of the dimensions of the prostate. A significant dose-dependent decrease (P < 0.05) in estradiol serum levels was observed in treated rats, whereas no significant modifications were found in testosterone serum levels. As fa r as prostatic steroid receptor concentrations were concerned, a significan t (P < 0.05) decrease in estrogen receptor number was observed in both trea ted groups, whilst a significant increase (P < 0.05) of androgen receptor c oncentrations was recorded only in rats treated with 20 mg mepartricin kg(- 1). Conversely, a dose-dependent up-regulation of both prostatic alpha (1)- and beta -AR was found. Data obtained suggest that the prostatic alpha (1) -AR expression may be strongly influenced by estrogen deprivation (mepartri cin treatment), therefore the combination of estrogen suppression (mepartri cin) and adrenergic suppression (alpha (1)-AR blockers) may be suggested as a possible pharmacotherapeutic strategy for the treatment of benign prosta tic hyperplasia. (C) 2001 Academic Press.