Some Pharmacological Studies onCitrullus colocynthis

The effects of chloroform and methanol extracts from the seeds of Citrullus colocynthis on glucose homeostasis was studied in normal and diabetic rats. In addition, some pharmacological effects of an ethanol extract of leaves (CCL) and the pulp (CCP) were also evaluated. Extracts of seeds had no effect on fasting glucose levels or in the oral glucose tolerance test in normal or diabetic rats. Both CCL and CCP resulted in spastic contractions of the rabbit jejunum which were not blocked by atropine. No effect was observed in the rat uterus. Both CCL and CCP potentiated the phrenic nerve-simulated diaphragm contractions of the rat. Both CCL and CCP also resulted in a dose independent, immediate increase in blood pressure followed by a rapid, short fall and subsequent increase in blood pressure that returned to normal levels in a short time. CCL and CCP reduced the heart rate and the force of contraction in isolated rabbit heart. At a dose 800 mg/kg of the ethanol extract, the leaves exhibited a secondary anti-inflammatory activity, but were severely toxic. At lower doses (100, 200, and 250 mg/kg), however, no anti-inflammatory activity was observed.