ABSTRACT
The aim of present study was to evaluate and compare the hypoglycemic activity of different solvents extracts of Thymus serpyllum in rabbits. Diabetes was induced with single intravenous injection of alloxan monohydrate [150mg/kg]. Glibenclamide and acarbose were used as standard drugs. The crude powder of Thymus serpyllum [500 mg/kg b.w] significantly reduced blood glucose level in both normal and diabetic rabbits. Various extracts of Thymus serpyllum were compared for their hypoglycemic activity in diabetic rabbits. Ether and aqueous extracts significantly reduced the blood glucose level with maximum effect [p<0.001] produced by aqueous extract, which was selected for further study. Aqueous extract significantly inhibited the rise in glucose level in oral glucose tolerance test. The extract showed synergistic effect with different doses of insulin; however serum insulin level of the diabetic rabbits was not significantly increased by the extract. HbA1c level was significantly [p<0.05] reduced whereas hemoglobin level was significantly increased in three months study. Phytochemical screening of the aqueous extract showed the presence of alkaloids, flavonoids, tannins, terpinoids, reducing sugar and cardiac glycosides. It is concluded that the aqueous extract might be used alone or in combination with insulin to manage diabetes and its associated complications
ABSTRACT
The cardiovascular activity of aqueous methanolic extract of Paspalidium flavidum L. was evaluated on isolated rabbit heart and aorta. Heart rates, force of contraction and perfusion pressure were assessed in the presence of different concentrations of extract and adrenaline by using Langendorff's technique. Moreover, the vasoconstriction effects were studied in rabbit aorta using isolated organ bath. The results indicated that the extract [1ng-100[micro]g/ml] exhibited a significant increase in heart rate, contractility and perfusion pressure of isolated rabbit's heart; with a maximum effect at 1ng/ml, which was comparable to adrenaline [1[micro]g/ml]. Similarly, adrenaline at doses from 1-10[micro]g/ml produced a significant dose dependant increase in all the cardiac parameters. The cardiotonic effects of the extract were significantly blocked by propranolol [10[-5]M] while an increase in perfusion pressure was completely antagonized by verapamil [10[-6]M]. Activity of cardiac marker enzymes was also significantly raised in the perfusate of isolated heart pretreated with the extract. In rabbit aorta, the extract exhibited a dose dependent vasoconstriction effect however it did not increase the tone of aorta when pre-treated with verapamil [10[-6]M]. It is conceivable therefore; that the cardiotonic and vasoconstriction effects of the extract might be due to its agonistic actions on beta-receptors and Ca[+2] channels