The Anti-ovulatory Effect of a Seed Extract of Ricinus Communis-linn

Antiovulatory effects of castor bean extract (CBE) were evaluated in cyclic female Sprague-Dawley rats. Adult cyclic female Sprague-Dawley rats on different days of the estrous cycle were administered 0.6g and 1.2g per kg body weight of an ether-soluble fraction of a methanolic extract of the castor bean (Ricinus communis-Linn) variation minor. The effects of these treatments on the length of the estrous cycle was studied by both the recording of vaginal smears daily and by direct visualization of oocyte-cumulus complexes on the ensuing day of estrus (10.00 h-12.00 h). Results showed that the drug has significant dose-dependent anti-ovulatory property and was more effective when administered before proestrus. The estrus cycle especially the dioestrus phase was significantly prolonged. Thus, CBE treatment significantly altered natural ovulation times. However there was resumption of normal estrus cycle 10 days after stopping the administration of CBE. Our results suggest that CBE altered the pattern of estrogen secretion/levels, and this led to delayed luteolysis. This finding plus distruption of the estrous cycle may be due to a direct effect on the ovary or the hypothalamo-hypophysial-ovarian axis. Many of these effects could be explained, in part, by interference with estrogen. We conclude that CBE is capable of direct actions to impair reproductive processes in female Sprague-Dawley rats. Key WordS:Ricinus Communis-linn, Ovulation, Seed Extract. [Nig. Jnl Health & Biomedical Sciences Vol.2(1) 2003: 31-34