Blebbistatin inhibits sphingosylphosphorylcholine-induced contraction of collagen-gel fiber populated by vascular smooth-muscle cells.
We prepared a cell-populated collagen-gel fiber including GbaSM-4 cells derived from the basilar artery of guinea pigs. This fiber tended to be a differentiated contractile phenotype in electron-microscope observations. Sphingosylphosphorylcholine (SPC) can induce contraction of the fiber (EC50 = 0.70 +/- 0.05 microM), and blebbistatin can inhibit the SPC-induced contraction (IC50 = 22.8 +/- 1.26 microM). Phosphorylation of the 20 kD myosin light chain (MLC20) significantly increased in GbaSM-4 cells provided with 1 microM SPC (P<0.05), which was maintained in the presence of 1 to 100 microM blebbistatin. These results suggest that vascular smooth muscle can relax even if MLC20 is phosphorylated.
Katayama
Takeshi
T
Department of Molecular and Cellular Pharmacology, Gunma University Graduate School of Medicine, Gunma, Japan. goukata@med.gunma-u.ac.jp
Yoshiyama
Shinji
S
Tanaka
Hideyuki
H
Wang
Hong Hui
HH
Nakamura
Akio
A
Kohama
Kazuhiro
K
D000818:Animals; D002478:Cells, Cultured; D003094:Collagen / Q000737:chemistry*; D005782:Gels; D006168:Guinea Pigs; D006576:Heterocyclic Compounds, 4 or More Rings / Q000494:pharmacology*; D008854:Microscopy, Electron; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D018994:Myosin Light Chains / Q000378:metabolism; D010767:Phosphorylcholine / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors / Q000494:pharmacology; D013110:Sphingosine / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors / Q000494:pharmacology
D005782:Gels; D006576:Heterocyclic Compounds, 4 or More Rings; D018994:Myosin Light Chains; C005356:sphingosine phosphorylcholine; D010767:Phosphorylcholine; C472645:blebbistatin; D003094:Collagen; D013110:Sphingosine