Anti-ovulatory activity of H₂ receptor blockers in albino rabbits – A preliminary study

Abstract

Objective To evaluate the anti-ovulatory activity of H₂ receptor blockers (ranitidine, famotidine and roxatidine) in albino rabbits considering the role of histamine in ovulation.

Method The drugs were orally administered once daily for three days to adult female rabbits weighing between 1.3–2.0 kg (four groups of three animals). The control group received the 1% weight/volume gum acacia suspension. Thirty minutes after the administration of the last dose, a freshly prepared 0.4 % solution of cupric acetate was administered to each animal intravenously via the marginal ear vein (4 mg/kg body weight) to induce ovulation. To assess ovulation, laparotomy was carried out 48 h after cupric acetate injection. The ovaries were exposed, bleeding points on each ovary were counted, and the ovaries and uteri were subjected to histopathological evaluation.

Results Based on the number of bleeding points (ovulation sites) observed on the ovary, H₂ blockers showed varying degrees of anti-ovulatory activity. Roxatidine exerted the most pronounced activity. Histopathological observations of uterus and ovary confirmed the aforementioned observations.

Conclusion H₂ receptor blockers appeared to inhibit the cupric acetate-induced ovulation in albino rabbits. Our results seem to confirm the role of histamine in ovulation reported by other authors.

Keywords:

• Anti-ovulatory
• Histamine
• H₂ blockers
• Famotidine
• Ranitidine
• Roxatidine

Acknowledgement

The authors acknowledge the University Grant Commission (UGC) for having funded this project (Grant No. F.7-47/2001(SR-1)).

Declaration of interest: The authors report no conflict of interest. The authors alone are responsible for the content and the writing of the paper.