Mitochondrial uncoupler carbonyl cyanide m-chlorophenylhydrazone induces vasorelaxation without involving K ATP channel activation in smooth muscle cells of arteries

• Published in: British journal of pharmacology 2016-11, Vol.173 (21), p.3145-3158
• Main Authors: Zhang, Yan-Qiu, Shen, Xin, Xiao, Xiao-Lin, Liu, Ming-Yu, Li, Shan-Liang, Yan, Jie, Jin, Jing, Gao, Jin-Lai, Zhen, Chang-Lin, Hu, Nan, Zhang, Xin-Zi, Tai, Yu, Zhang, Liang-Shuan, Bai, Yun-Long, Dong, De-Li
• Format: Article
• Language: English
• Subjects: Animals; Arteries - cytology; Arteries - drug effects; Carbonyl Cyanide m-Chlorophenyl Hydrazone - chemistry; Carbonyl Cyanide m-Chlorophenyl Hydrazone - pharmacology; Dose-Response Relationship, Drug; KATP Channels - metabolism; Male; Mitochondria - metabolism; Myocytes, Smooth Muscle - drug effects; Rats; Rats, Sprague-Dawley; Structure-Activity Relationship; Uncoupling Agents - chemistry; Uncoupling Agents - pharmacology; Vasodilation - drug effects
• ISSN: 0007-1188; 1476-5381
• DOI: 10.1111/bph.13578

The effects and mechanisms of chemical mitochondrial uncouplers on vascular function have never been identified. Here, we characterized the effects of the typical mitochondrial uncoupler carbonyl cyanide m-chlorophenylhydrazone (CCCP) on vascular function in rat mesenteric arteries and aorta and elucidated the potential mechanisms. Isometric tension of mesenteric artery and thoracic aorta was recorded by using a multiwire myograph system. Protein levels were measured by western blot analyses. Cytosolic [Ca ] , mitochondrial ROS (mitoROS) and mitochondrial membrane potential of smooth muscle cells (A10) were measured by laser scanning confocal microscopy. Acute treatment with CCCP relaxed phenylephrine (PE)- and high K (KPSS)-induced constriction of rat mesenteric arteries with intact and denuded endothelium. Pretreatment with CCCP prevented PE- and KPSS-induced constriction of rat mesenteric arteries with intact and denuded endothelium. Similarly, CCCP prevented PE- and KPSS-induced constriction of rat thoracic aorta. CCCP increased the cellular ADP/ATP ratio in vascular smooth muscle cells (A10) and activated AMPK in A10 cells and rat thoracic aorta tissues. CCCP-induced aorta relaxation was attenuated in AMPK α1 knockout (-/-) mice. SERCA inhibitors thapsigargin and cyclopiazonic acid (CPA) but not the K channel blocker glibenclamide partially inhibited CCCP-induced vasorelaxation in endothelium-denuded rat mesenteric arteries. CCCP increased cytosolic [Ca ] , mitoROS production and depolarized mitochondrial membrane potential in A10 cells. FCCP, the analogue of CCCP, had similar vasoactivity as CCCP in rat mesenteric arteries. CCCP induces vasorelaxation by a mechanism that does not involve K channel activation in smooth muscle cells of arteries.