Contractile Effects of Methanol Extract of Tacazzea apiculata Stem on Albimo Rats Uterine Strips

Abnormalities of uterine contractions during labour has been associated with many complications during childbirth including postpartum heamorrhage which may lead to maternal mortality. People use different medicinal plants to augment labour and to achieve a better outcome due to accessibility and affordability of such plants. Tacazzea apiculata stem has been in use for induction of labour at parturition in the Northern part of Nigeria but there is no scientific evidence backing up its use for this purpose. Hence, this study research the effect of the plant on uterus smooth muscle contractions in comparison with standard uterotonic agents such as oxytocin, prostaglandin, acetylcholine and potassium chloride in-vitro. The phytochemicals analysis was done using standard methods for such purpose. Cold methanol maceration was used for extraction. The LD50 was determined using Lorke’s method. The uterus smooth muscle contractility activity of Tacazzea apiculata stem was determined by isolating the uterine strips of albino rats mounted in an organ bath connected to a power lab. Different concentrations of both the plant extract and standard uterotonics were administered. The methanol extract of Tacazzea apiculata stem contained alkaloids, flavonoids, saponins, tannins, steroids, terpenoids, and quinones. Acute toxicity studies revealed that the LD₅₀ of the extract exceeded 5000 mg/kg, indicating a wide margin of safety. The extract elicited concentration-dependent contractions of the non-pregnant rat uterus. At concentrations ranging from 160 to 640 µg/ml, the extract demonstrated uterotonic activity comparable to standard agents, though effective at relatively higher doses. Statistically significant differences were observed between the response to the extract at 160 µg/ml and those of oxytocin (0.064 µg/ml), prostaglandin (6.4 × 10⁻⁴ µg/ml), acetylcholine (64 × 10⁻⁴ µg/ml), and potassium chloride (6.4 × 10⁻³ µg/ml). Additionally, a significant difference was noted between the extract at 160 µg/ml and 640 µg/ml. The methanol extract of Tacazzea apiculata stem exhibited significant uterotonic activity, likely attributable to its diverse phytochemical constituents, including alkaloids, flavonoids, and saponins.