Effect of mesocarb-theophylline combination on gonadal and gonadotropic hormone levels in male and female rats.

The effects of mesocarb-theophylline combination given p.o. for 30 days on plasma levels of gonadal and gonadotropic hormones (testosterone, estradiol, progesterone, FSH, LH and prolactin) were studied in male and female Wistar rats and compared to the effects of the drugs given alone. In male animals theophylline alone and mesocarb-theophylline combination did not affect normal plasma concentrations of hormones. Mesocarb alone (20 mg/kg) slightly lowered FSH levels, but with the addition of 100 mg/kg theophylline, levels returned to normal. The effects of mesocarb on FSH levels in female animals were similar but slightly stronger. In addition to its effects on FSH, a decrease in prolactin levels was also observed. These changes were not pathological while there were no changes in estradiol and progesterone levels. The combination mesocarb-theophylline prevented the oppressive effect of mesocarb on FSH secretion, did not alter FSH, LH and prolactin secretion from the adenohypophysis, and did not alter the levels of the gonadal hormones estradiol and progesterone in female animals and testosterone in males.