Anti-Ovulatory Effect Of Ricinine-Enriched Extract Of R.Communis In Female Wistar Rats

Abstract

Anti-ovulatory drugs are the antifertility agents that induce infertility by suppressing ovulation. The gonadosomatic index (GSI) is the ratio between the weight of the gonads and the total weight of the individual. The GSI has been previously used as a criterion for evaluating the development and function of ovaries in animal models. Traditionally, medicinal plants have been used in the control of fertility, which are believed to be associated with less health risks compared with the orthodox medicine. Ricinine, an alkaloid of the R. communis plant, has shown some antifertility properties, however, its effects on ovulation are yet to be investigated. This research is aimed at evaluating the contraceptive effects of the Ricinine-enriched extract of R. communis in female Wistar rats. Twenty-five (25) female Wistar rats of about 8-10 weeks weighing 100-150 g, whose estrous cycle have been confirmed by the vaginal smear examination method, were weighed and grouped into 5 groups (n=5). The animals received 1 ml/kg distilled water, 0.6 mg/kg Combined Oral Contraceptives (COCs), 100 mg/kg RCN, 200 mg/kg RCN and 400 mg/kg RCN for group I-V respectively orally daily for 15 days. The animals were euthanized on the 16th day and the ovaries and uteri were removed and weighed immediately for the calculation of the gonadosomatic index ([gonad weight/body weight] x 100%). The ovaries were suspended in normal saline and the number of ovulation points and matured follicles were counted. No significant difference was observed for the mean gonadosomatic index of the female rats in all the experimental groups (0.373±0.04, 0.495±0.12 and 0.570±0.04) when compared with the control (0.443±0.08) (p<0.05). For the results on ovulation count, there was a significant decrease in the number of ova observed at all doses of the RCN (2.00±0.41, 0.75±0.48, and 0.50±0.29 respectively) compared with the control group (5.25±0.63) (p<0.05). In conclusion, the study showed that the Ricinine-enriched extract of R.communis has an anti-ovulatory effect by decreasing the number of ovulation points and matured follicles but no significant effect on the gonadosomatic index.

Keywords: anti-ovulatory, antifertility, gonadosomatic index, Ricinine, R.communis