Pharmacological activities of Grewia bicolor roots.

Intraperitoneal administration of the ethanol extract of Grewia bicolor root (300 mg/kg) to rats in early pregnancy (+1-4 days) did not affect the number of conception sites, but significantly increased resorption. In late pregnancy (+19-20 days), the extract (300 mg/kg) did not affect duration of the gestation period; however, 400 mg/kg was lethal to all mother rats. The active compound, apparently a peptide, exerted a serotonin-like effect on rat uterus, rat fundus and rabbit jejunum. All these effects were abolished by methysergide. A transient serotonin-like rise in cat blood pressure was produced by the active fraction and this effect was also blocked by cyproheptadine.