Chronic intermittent hypobaric hypoxia enhances vasodilative effects of paeonol on isolated thoracic aorta rings of rats
10.3969/j.issn.1001-1978.2014.11.019
- VernacularTitle:慢性间歇性低压低氧增强丹皮酚舒张大鼠动脉的作用
- Author:
Zan GUO
;
Shijun SONG
;
Shuang SONG
;
Kun MA
;
Lei YU
;
Yanli SONG
;
Huijie MA
;
Yi ZHANG
- Publication Type:Journal Article
- Keywords:
chronic intermittent hypobaric hypoxia ( CIHH);
paeonol;
thoracic aortic rings;
vasodilation;
ATP-sensitive potassium channel;
rat
- From:
Chinese Pharmacological Bulletin
2014;(11):1574-1579
- CountryChina
- Language:Chinese
-
Abstract:
Aim To investigate the effect of chronic intermittent hypobaric hypoxia ( CIHH) on the paeonol induced vasomotion of isolated rat ’ s thoracic aorta rings and its underlying mechanisms. Methods Spra-gue-Dawlay ( SD ) rats were randomly divided into 2 groups: control group ( CON ) and CIHH treatment group ( CIHH) . CIHH rats were exposed to hypoxia in a hypobaric chamber simulating 5 000 m altitude, 6 hours daily for 28 days. CON rats lived in the same en-vironment as CIHH animals except hypoxia. Organ bath technique was used to observe the effect of pae-onol on isolated thoracic aorta rings of rats. Results There were no significant differences of noradrenaline ( NE )- and KCl-induced contraction in thoracic aorta rings among CIHH and CON rats;CIHH enhanced va-sodilative effects of paeonol on isolated thoracic aorta rings of rats; the vasodilative effects on CIHH rats could be partly decreased by β-receptor blocker prop-ranolol,ATP-sensitive potassium channel ( KATP ) bloc-ker glibenclamide and NO synthase inhibitor L-NAME. Paeonol significantly inhibited NE-induced intracellular and extracellular calcium-dependent contraction in CIHH rats. Paeonol didn ’ t inhibit NE-induced con-traction by intracellular calcium release and its inhibi-tory effect couldn ’ t be blocked by glibenclamide in CON. Vasodilative effects of paeonol couldn ’ t be re-versed by indomethacin, a cyclooxygenase inhibitor, in CIHH and CON rats. Conclusion CIHH significantly enhances vasodilative effects of paeonol on isolated tho-racic aorta rings of rats. Besides promoting the signa-ling pathway of paeonol in CON, CIHH significantly enhances vasodilative effects of paeonol via activating KATP and inhibiting Ca2+ release from sarcoplasmic re-ticulum.
