Igwe Kalu Kalu, Ijeh Ifeoma.Irene. and Okafor Polycarp.N.
AIMS: To determine the action of contractile fraction of Vernonia amygdalina.Del ethanol extract on hormonal profile of Estrogen and Progesterone in female albino Winstar rats. Methodology: Ethanol crude extract of Vernonia amygdalina was fractionated into six (F1, F2, F3, F4, F5, and F6). The different fractions were subjected to in vitro screening to provide preliminary observations required to select the crude plant extract with the best contractile properties for further investigations. Using physiograph uterine tissue contractile amplitudes were determined at 0.25 mg/ml, 0.3 mg/ml, 0.7 mg/ml, 1.0mg/ml, 1.25mg/ml and 1.5mg/ml for the different fractions. Fraction F5 had the best contractile response on isolated uterine tissue in the presence of agonist ACh. F5 was used for further studies on profile of Estrogen and Progesterone. Adult female albino Wistar rats grouped into five (I, II, III, IV, V) were used for the hormonal study. Group I served as negative control and was administered 20% dimethyl sulphoxide (DMSO) while groups II, III, and IV served as test groups and were administered 40mg/kg, 80mg/kg and 120mg/kg body weight of F5 respectively. Group V was oxytocin treated group which served as positive control and was administered 0.1 µg of oxytocin intra-peritopeally. Results: After 5 days of administration of F5, the serum estrogen and progesterone concentrations in the serum were measured. There was a dose dependent increase in the serum estrogen levels (491.66±0.08 pg/ml, 616.66±2.02 pg/ml and 673.66±2.02 pg/ml) in the test groups which was significantly higher than the negative control (92.66±0.88 pg/ml). The results showed a dose dependent significant (P<0.05) decrease in serum progesterone in groups II, III and IV (58.33±0.88 µg/ml, 40±0.59 µg/ml, and 35.3.66±0.52 µg/ml,) when compared to the negative control (61.33±2.40 µg/ml) Conclusion: The contractile extract fraction (F5) increased the serum concentration of estrogen in the rats but decrease the progesterone concentration significantly in dose dependent fashion. This supports the concomitant rise in estrogen and fall in progesterone occurring just before parturition.