title: [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].
abstract: OBJECTIVE
  Phosphorylation 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.
  
  
  METHODS
  Segments 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.
  
  
  RESULTS
  Intracoronary 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).
  
  
  CONCLUSIONS
  Rho-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.
authors.affiliation: Department of Cardiology, First Affiliated Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Qi-gang
authors.initials: QG
authors.lastname: Guan
authors.forename: Ding-yin
authors.initials: DY
authors.lastname: Zeng
authors.forename: Xi-zhuo
authors.initials: XZ
authors.lastname: Sun
authors.forename: Zhi-Lin
authors.initials: ZL
authors.lastname: Miao
authors.forename: Xu-chen
authors.initials: XC
authors.lastname: Zhou
authors.forename: Xue-zhi
authors.initials: XZ
authors.lastname: He
authors.forename: Feng-tong
authors.initials: FT
authors.lastname: Han
authors.forename: Ying
authors.initials: Y
authors.lastname: Cheng
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
mesh_terms: D000818:Animals; D003329:Coronary Vasospasm / Q000378:metabolism* / Q000473:pathology; D004195:Disease Models, Animal; D053583:Interleukin-1beta / Q000009:adverse effects* / Q000378:metabolism; D008297:Male; D018994:Myosin Light Chains / Q000378:metabolism*; D010766:Phosphorylation; D012333:RNA, Messenger / Q000378:metabolism; D013552:Swine; D054460:rho-Associated Kinases / Q000378:metabolism*
chemical_list: D053583:Interleukin-1beta; D018994:Myosin Light Chains; D012333:RNA, Messenger; D054460:rho-Associated Kinases