Effect of melatonin on blood pressure and aortic relaxation and contraction activity from hypertensive rats
- Author:
Yu-Sheng WEI
1
Author Information
1. School of Life Science, Lanzhou University
- Publication Type:Journal Article
- Keywords:
Isolated vessel ring;
Melatonin;
Renovascular hypertention;
Thoracic aorta
- From:
Chinese Pharmacological Bulletin
2002;18(1):46-50
- CountryChina
- Language:Chinese
-
Abstract:
AIM: To observe the hypotensive effect of melatonin (MT) on two-kidney one-clip renal hypertensive (2K1C) rats and to explore its aortic mechanism. METHODS: 2K1C rats were obtained by narrowing the left kidney artery; systolic blood pressure was measured by use of tail-cuff method; vascular actions of MT were measured using isolated blood vessel method. RESULTS: MT reduced blood pressure of 2K1C rat significantly [(C23.45 ± 2.40) kPa versus (19.81 ± 2.78) kPa, P < 0.05]; MT (10-4 mol • L-1), restored vasodilation to acetyl-choline partially (P < 0.01) and attenuated vasoconstriction to norepinephrine (P < 0.05) in isolated aortic rings from 2K1C rats. MT(10-5 ∼ 10-3 mol • L-1) also inhibited vasoconstriction of aortic rings to KCl (70 mmol · L-1) and this action had no significant difference in sham and 2K1C rats. CONCLUSION: Vascular activities of MT is one of the factors involved in its hypotensive effect. MT restores the endothelial dysfunction and the balance of oxidative condition in smooth muscle cell by its free radical scavenging and antioxidant properties.
