iridoids and arginine-methyl-ester

The mechanism of oleuropein's antihypertensive effects was examined in rat model of simultaneous type 2 diabetes and renal hypertension (diabetic hypertensive). Five groups of male Sprague-Dawley rats including a control, a diabetic-hypertensive group receiving vehicle, and three diabetic-hypertensive groups receiving oleuropein at 20, 40, or 60 mg/kg/day were used. The duration of diabetes was 10 weeks; during the last 4 weeks of which, animals were hypertensive and received vehicle or oleuropein. Systolic blood pressure, glucose and malondialdehyde, heart rate, and maximal response to phenylephrine (PE) in the absence of nitro-L-arginine methyl ester (L-NAME) of oleuropein-treated groups were significantly lower than those of vehicle-treated group. Erythrocyte superoxide dismutase, maximal response to PE in the presence of L-NAME, and maximal response to acetylcholine (Ach) of oleuropein-treated groups were significantly higher than those of vehicle-treated group. The findings indicate that antihypertensive effects of oleuropein might be partly mediated by improving the release of nitric oxide, and antioxidant and sympathoplegic activities.

Topics: Acetylcholine; Animals; Antihypertensive Agents; Arginine; Blood Glucose; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 2; Disease Models, Animal; Endothelium, Vascular; Hypertension, Renal; Iridoid Glucosides; Iridoids; Male; Molecular Structure; Nitric Oxide; Rats; Rats, Sprague-Dawley; Superoxide Dismutase