PHARMACOLOGICAL STUDIES ON THE ANTIFERTILITY EFFECTS OF RICOM-1013-J FROM RICINUS-COMMUNIS VAR MINOR AND PRELIMINARY CLINICAL-STUDIES ON WOMEN VOLUNTEERS

The seed and petroleum ether fraction (PE; 5-20 mg/kg) of RICOM-1013-J demonstrated high antifertility efficacy in both animals anal in wome n volunteers, Although PE demonstrated some oestrogenic activity in ov ariectomized immature rats, there was no evidence of progestational ac tivity, Administration of PE (5-20 mg/kg, s.c.) to rats and rabbits al tered the activity profile of the uterus and fallopian tube from day 3 to day 90 of pretreatment, Moreover, the responsiveness of the uterin e muscle and the fallopian tube to Ach, oxytoxin and ergometrine was s ignificantly reduced from day 28 to day 90, Furthermore, PE induced hi stological changes in the ovary and altered the oestrous cyclicity, Th ese results suggest that the high antifertility efficacy of RICOM-1013 -J is unlikely to be due: to any direct progestational activity and ma y be due partly to alteration in oestrogen/progesterone balance as wel l as to a direct effect on the uterus and fallopian tube. A survey of the contraceptive efficacy in women volunteers administered orally thr ee seeds of RICOM-1013-J demonstrated the high efficacy of the seed in protecting against pregnancy for a period of 12 months with high comp liance and minimal side effects, There was no evidence of side effects (nausea, vomiting, weight gain, morning sickness, increased blood pre ssure, etc) attributable to oestrogen in oral contraceptives; and thes e results may indicate a novel contraceptive effect due to both hormon al and direct effects on the reproductive system. (C) 1997 John Wiley & Sons, Ltd.