Evaluation of Cardioprotective effect of Coleus forskohlii against Isoprenaline induced myocardial infarction in rats.

Coleus forskohlii is an important ancient root drug of Indian origin, commonly known as gander in indian ayurvedic system of medicine. A lot of research work has been done on Coleus forskohlii regarding various cardiovascular disorders but no work has been done to find out its cardioprotective activity. Wistar albino rats were divided into five main groups having 5 animal each: Group 1 termed as Normal control (NC) received 0.5ml of normal saline throughout experimental period and served as control. Group 2 termed as Isoprenaline group (ISO) received 0.5ml of normal saline for 28 day and received Isoprenaline (85mg/kg, s.c.) on 29th and 30th day at an interval of 24 hours. Group 3 termed as Standard group (STD) received Metoprolol (pure) (10 mg/kg/day, p.o.) for 28 day and received Isoprenaline (85mg/kg, s.c.) on 29th and 30th day at an interval of 24 hours. Group 4 termed as Test group 1 (TG 1) & Group 5 termed as Test group 2 (TG 2) received Coleus forskohlii (50 mg/kg/day, p.o.) (100 mg/kg/day, p.o.) for 28 day and received Isoprenaline (85mg/kg, s.c.) on 29th and 30th day at an interval of 24 hours respectively. The experiment was terminated on 31st day and animal were sacrificed by cervical decapitation after an overnight fast. Blood was collected for estimation of biochemical parameter and heart was dissected out for grading, heart/weight ratio and histopathological examination.the the level of marker enzyme in serum as AST, ALT, LDH, CK, Troponin-I were significantly decreased (P<0.001) in rats pretreated with Coleus forskohlii when compared to that of group which received isoprenaline alone. Further, histopathological examination showed the reduction of necrosis, edema and inflammation following Coleus forskohlii pretreatment. Based on present findings, it is concluded that Coleus forskohliil may be a potential preventive and therapeutic agent against the myocardial necrosis associated ischemic heart disease.

Increased brainstem angiotensin-I levels in chronic 2 KIC hypertensive rats.

A study was undertaken on the role of brainstem renin-angiotensin system in maintenance of hypertension in chronic renovascular hypertensive rats. Hypertension was induced by unilateral renal artery clamping, while the contralateral kidney was left intact (2 KIC). Blood pressure (BP), plasma renin activity (PRA) and brainstem angiotensin (ang-I) levels were measured after 24 days, in hypertensive and sham-operated animals. In separate subgroups of these animals, the effect of intracerebroventricular administration of captopril on the parameters listed was studied. The results showed high ang-I levels in 2 KIC rats as compared to controls (P less than 0.05). Captopril administration (500 micrograms/50 microliters icv) caused a fall in BP and increase in brainstem ang-I levels (P less than 0.01). In control animals, however, captopril produced a rise in BP without any significant change in brainstem ang-I levels. Peripheral plasma renin activity was normal, despite significant sodium retention in 2 KIC rats. The results are suggestive of activation of brainstem renin-angiotensin system (RAS) in chronic 2 KIC hypertension.

Some aspects of pharmacological profile of sodium curcuminate.

Rapid i.v. injection of sodium curcuminate (NaC) produced transient hypotension and bradycardia in anaesthetized dogs and cats which were not blocked by bilateral vagotomy, atropine, mepyramine or propranolol. In open-chest anaesthetized cats, decrease in blood pressure and heart rate was accompanied by simultaneous transient reductions in left ventricular systolic pressure, maximal rate of rise of left ventricular pressure and a concomitant increase in left ventricular end-diastolic pressure. It was concluded that the transient hypotensive effect of NaC is due to its myocardial depressant action. NaC exhibited negative inotropic and chronotropic effect on isolated perfused rabbit heart, an antispasmodic effect on smooth muscle of dog s intestine in vivo and of vas deferens of guinea-pig in vitro but no effect on the rectus abdominis muscle of frog or its response to cholinergic stimulation.

Anti-spasmogenic effect of cyproheptadine on guinea-pig ileum.

Antagonistic activity of cyproheptadine against common spasmogens, like acetylcholine, histamine, serotonin, bradykinin and angiotensin, was studied on isolated guinea-pig ileum. Cyproheptadine produced a reversible antagonism of non-competitive type and was most effective against serotonin. It was less potent against histamine, bradykinin and angiotensin and least potent against acetylcholine.