Smooth muscle relaxant evaluation of Jatropha curcas Linn (Euphorbiaceae) and isolation of triterpenes.

Jatropha curcas is a herbal preparation used in the tropics for the treatment of threatened abortion and related problems associated with pregnancy. The Stem bark of Jatropha curcas is used ethno medicinally in Nigeria especially in the eastern part of the country for the treatment of infertility and spontaneous abortion (miscarriage). The present study was undertaken in order to validate the folkloric claim, using scientific experimental procedures and bioassay guided fractionation. The crude powdered sample was subjected to phytochemical screening testing for the presence of alkaloids, tannins, saponins and carbohydrates. Chromatographic analysis (TLC and VLC) were carried out using various solvent systems. The effect of methanolic extracts on rat uterine contractions was studied in vitro, in 40ml organ baths containing physiological salt solution of De Jalon maintained at 370C, aerated with 95% O2 and 5% CO2 with an isometric transducer connected an UgoBasile recorder under a resting tension of 750mg. The result of the phytochemical screening revealed the presence of glycosides, tannins, saponins and alkaloids. The extract abolished significantly the spontaneous contraction of the uterus and reduced acetylcholine induced uterine contractions at a dose of 50mg/ml. The tocolytic effects indicate the presence of active principle(s) which would explain the ethno medicinal use of the stem bark of Jatropha curcas to treat spontaneous abortion.

Antidiarrheal evaluation of the ethanol extract of Nauclea latifolia root bark.

Nauclea latifolia (Rubiaceae) is a medicinal plant used in Nigeria folk medicine for the treatment of gastrointestinal disorders. The root bark of the plant was extracted with 70% ethanol and the extract screened for antidiarrheal activity by investigating castor oil-induced diarrhea and small intestinal motility in mice. The effects of the extract on isolated rat ileum were also investigated. The extract (125, 250 and 500 mg/kg) caused a significant decrease in the frequency of diarrhea and conferred protection following castor oil administration (P < 0.05). It also significantly (P < 0.0001) inhibited small intestinal motility in mice at the same doses. Its activity was dose-dependent and when compared to atropine, its antidiarrheal effects at 500 mg/kg were 179% and 165% respectively, in castor oil-induced diarrhea and small intestinal motility experiments. Extract effects on rat ileum revealed a significant (P < 0.0001) inhibition of acetylcholine-induced contractions at 0.2 and 2 mg/mL final bath concentrations used. These findings confirm the antidiarrheal activity of the root bark extract of N. latifolia.

Antidiarrheal evaluation of the ethanol extract of Musanga cecropioides stem bark.

The ethnomedicinal uses of Musanga cecropioides R. Apud Tedlie (Cecropiaceae) as a hypotensive agent have been scientifically investigated and reported. This work examines its effect on various models of diarrhea based on the ethnomedicinal use of the plant for this indication. The stem bark of the plant, used locally by soaking in gin (alcoholic), was treated with absolute ethanol and the extract screened for antidiarrheal activity using the castor oil-induced diarrhea and small intestinal motility models in mice. Its effects on the isolated rat ileum were also investigated. In the castor oil-induced diarrhea, the extract at 100, 200, and 400 mg/kg significantly (P < 0.05 at all doses) showed dose-related antidiarrheal effects as indicated by reduction in the number and weight of fecal material produced. The extract at all doses used also significantly (P < 0.05, P < 0.0001 and P < 0.0001 at 100, 200, and 400 mg/kg doses, respectively) decreased the intestinal motility of the treated mice as compared to controls and inhibited acetylcholine-induced contractions (P < 0.0001). In the isolated rat ileum the extract at 5 and 10 mg/mL, remarkably inhibited acetylcholine induced contractions, indicating a probable antimuscarinic effect of the extract. The results obtained confirmed that the stem bark of M cecropioides has antidiarrheal activity as used in folkloric medicine.

Preliminary studies of blood pressure lowering effect of Nauclea latifolia in rats

Roots of Nauclea latifolia are used in Nigeria for the treatment of hypertension. Ethanolic extract of the root of N. latifolia was administered to anaesthetised rats through the jugular vein while the blood pressure was measured through the carotid artery. The extract reduced systolic, diastolic, and mean arterial pressure in normotensive and in one kidney one clip hypertensive rats in a dose dependant manner. 10 mg/kg of the extract reduced the mean arterial pressure from 115.7 ± 0.4 to 99.6 ± 3.8 mm Hg, while it reduced the systolic and diastolic from 125.6 ± 0.5 to 102.4 ± 4.0 and from 110.5 ± 0.3 to 95.0 ± 3.2 mm Hg respectively. The changes caused in hypertensive rats were much greater. The same dose of the extract reduced the mean arterial pressure from 157.4 ± 4.7 to 72.0 ± 3.6 mm Hg, while it reduced the systolic and diastolic blood pressures from 180.0 ± 5.7 to 90.1 ± 2.6 and from 146.2 ± 3.3 to 63.0 ± 4.9 mm Hg respectively. The extract (10 mg/kg) also reduced the heart rate of normotensive rats from 365 ±12.8 to 280 ± 6.0 beats/min, while it reduced the heart rate of hypertensive rats from 550 ± 22.5 to 120 ± 8.0 beats/min. The reduction in blood pressure and heart rate was not affected by prior treatment with atropine or promethazine

Phytochemical components of Hunteria umbellata (K. Schum) and its effect on isolated non-pregnant rat uterus in oestrus.

Hunteria umbellate plant is used by West African traditional midwives as phytomedicine in herbal remedies to treat pregnancy related ailment and most especially to augment or induce labour in gravid uterus. The purpose of this study was to investigate this claim with view to validating scientifically the ethno - medicinal usage. The phytochemical analysis of the crude medicinal plant extract revealed the presence of saponin, saponin glycosides, steroid, tannins, volatile oils, phenols and copious amount of alkaloids. The aqueous extract obtained by maceration technique was subjected to pharmacological testing in vitro on a piece of isolated rat uterus previously pretreated with stilbesterol, suspended in De Jalon at 37 degrees C and aerated with 95% Oxygen and 5% CO(2). The oxytocic activity of the aqueous pulp extract of the pulp of Hunteria umbellata was compared with uterine stimulant like oxytocin. The extract affected the contractility of the uterus significantly (P<0.05) in a dose dependent manner. The effect of 10mg/ml extract was blocked by 0.1 ml of 0.1mg/ml atropine. The extract also potentiated the response shown by various doses of oxytocin. This preliminary investigation revealed that Hunteria umbellata has oxytocic effect thus justifying the use by the traditional birth attendants.

Phytochemical and active column fractions of Pyrenacantha staudtii leaf extracts on isolated rat uterus.

Four methanolic leaf fraction extracts of Pyrenacantha staudtii obtained from accelerated gradient chromatography (AGC) were tested on the isolated rat uterus. Various fractions--M1, M2, M3 and M4 through bioassay guided isolation were obtained. Fractions M(2) and M(4), containing saponins and alkaloids respectively, significantly (P<0.05) exerted high smooth muscle relaxant activity on the uterus. Fractions M(1) and M(3) containing fatty acids and tannins respectively did not exhibit significant effect on the isolated rat uterus. The results indicate the presence of active principles in the leaf extracts of P. staudtii which may be responsible for some of the applications in traditional medicines as remedy against threatened abortion and dysmenorrheal.