Inhibition of steroid sex hormones release in rats by two Ca2+ channel blockers

The calcium channel blockers Diltiazem HCl (2 mg kg-1 day-1, IP) or Cinnarizine (8 mg kg-1 day-1, IP) were given for a period of 30 days to adult male and female albino rats. The effect of each calcium channel blocker on circulating blood levels of steroid sex hormones was investigated by radioimmunoassay in comparison with the normal control level. The data demonstrated that both Diltiazem and Cinnarizine significantly decreased serum normal testosterone levels in males (36% and 52% inhibition respectively) as well as both normal estradiol and progesterone contents in females (58% and 45% inhibition with Diltiazem and 68% and 52% inhibition with Cinnarizine respectively). This study indicates the importance of blood sex hormones-follow up in case of long term Ca2+ channel blockers medication.