TOCOLYTIC

The traditional use of Momordica charantia (bitter melon) includes the treatment of various ailments, notably diabetes, and its application as an abortifacient and contraceptive. Reports that its seeds can induce uterine contractions raise concerns regarding its safety during
pregnancy. This study was therefore conducted to investigate the effect of the M. charantia leaf extract on the isolated uterus of non-pregnant mice. Hydro-alcoholic extract was obtained from extracting the powdered leaf material with Hydro-ethanol (1:1) solvent using a Soxhlet
apparatus. Twenty-five non-pregnant albino mice were used, and those in the estrus phase (identified by vaginal smears) were sacrificed by cervical dislocation. Uterine strips were isolated, cleaned, mounted in a 10 ml organ bath containing aerated physiological saline
solution maintained at 37∘C, and subjected to a 40-minute equilibration period with 0.5 g resting tension. Changes in isometric contractions were recorded using LabChart Software. The M. charantia leaf extract (0.00625 – 0.4 mg/mL) was added cumulatively to assess its
effects on spontaneous, oxytocin-induced (14 nM), and high potassium-induced contractions (80 mM) as well as oxytocin-induced contractions in a calcium-free medium. Data were analyzed using one-way ANOVA with Dunnett’s post hoc test (p<0.05). The leaf extract of M.
charantia inhibited spontaneous uterine contractions in a concentration-dependent manner, causing a significant decrease in the force of contraction(amplitude) but not the frequency. The extract also significantly and concentration-dependently decreased the force of contractions
induced by both oxytocin and high potassium, again with no observable changes in contraction frequency. However, the extract did not significantly alter oxytocin-induced contractions when tested in a calcium-free medium. In conclusion the inhibitory effect of M. charantia leaf extract on both spontaneous and induced uterine contractions suggests a calcium-dependent
mechanism. This mechanism likely involves the blockade of calcium influx from the extracellular compartment rather than the inhibition of intracellular calcium release, offering insight into the plant's traditional use and potential pharmacological targets.

It has been reported (Umoh 1998), that the peppery fruits of Dennettia tripetala usually find application in food meant for pregnant women. Moreover, Dennettiatripetala seeds are very important in the diets of women after childbirth, during which time it is claimed that spices and herbs aid the contraction of the uterus (Achinewhel et al., 1995). The uterine activities of this important fruit have not been fully documented. Little is known of the uterine activity of Dennettiatripetalafruit despite its widespread multipurpose uses as food and drugs. The present study was designed to determine the uterine activity of Dennettiatripetala fruit and, consequently.The cumulative concentrations (0.01-12.21 mg/ml) of the methanolic extract of DT was tested on rhythmic spontaneous uterine contraction, while the most potent concentration 3.5 mg/kg of DT extract was tested on oxytocin (OT), high potassium chloride (KCl)-induced uterine contractions and OT-induced uterine contractions in a calcium deprived state. DT extract produced significant (P<0.05) decrease in the frequency and amplitude of spontaneous contractions with IC50 of 0.99 ± 0.06 and 0.83 ± 0.40 mg/ml respectively. As well as OT (11.62 nM)-induced frequency of myometrial contractions and OT (11.62 nM)-induced contractions in calcium deprived state containing ethylenediaminetetraacetic acid (EDTA), and significant changes on high KCl (80 mM)-induced myometrial contractions. These observations may explain the effect of DT and its folkloric use in the food of pregnancy women, however further studies are advised to know the direct mechanism of action and to characterize and isolate specific bio-constituents responsible for the observed effects.