Upregulated Rho-kinase and increased phosphorylation of myosin-binding subunit of myosin phosphates are key players in a porcine coronary artery spasm model with interleukin-1beta.
- Author:
Qi-gang GUAN
1
;
Ding-yin ZENG
;
Xi-zhuo SUN
;
Zhi-Lin MIAO
;
Xu-chen ZHOU
;
Xue-zhi HE
;
Feng-tong HAN
;
Ying CHENG
;
Li ZHANG
Author Information
- Publication Type:Journal Article
- MeSH: Animals; Coronary Vasospasm; metabolism; pathology; Disease Models, Animal; Interleukin-1beta; adverse effects; metabolism; Male; Myosin Light Chains; metabolism; Phosphorylation; RNA, Messenger; metabolism; Swine; rho-Associated Kinases; metabolism
- From: Chinese Journal of Cardiology 2006;34(1):50-53
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVEPhosphorylation of myosin light chain (MLC) is one of the most important steps for vascular smooth muscle contraction and Rho-kinase is involved in this process. We investigated the role of Rho-kinase in a porcine coronary artery spasm model with interleukin-1beta.
METHODSSegments of left coronary artery adventitia were surrounded by normal saline (n = 8) or IL-1beta agarose microne (n = 8) for 2 weeks. Vasospastic responses to intracoronary serotonin or histamine then studied at the saline or IL-1beta-treated site. The Rho-kinase mRNA expression in the treated site was measured by reverse transcription-polymerase chain reaction analysis (RT-PCR). The extent of phosphorylation of myosin-binding subunit of myosin phosphates (MBS, one of the major substrates of Rho-kinase) were quantified by Western blot analysis.
RESULTSIntracoronary serotonin or histamine repeatedly induced coronary artery spasm and coronary arterial stenosis was evidenced at IL-1beta-treated site. Expression of Rho-kinase mRNA in IL-1beta-treated site was significantly increased compared to saline treated site (98.20% +/- 7.66% vs. 63.70% +/- 4.26%, P < 0.05). Western blot analysis showed that during the serotonin-induced contractions the extent of phosphorylation of MBS was also significantly increased in the spastic site (25,485 +/- 4745 vs. 6510 +/- 779, P < 0.05).
CONCLUSIONRho-kinase upregulation at the spastic site and increased phosphorylation of myosin-binding subunit of myosin phosphates are key players in inducing vascular smooth muscle hypercontraction in this porcine model.