pubmed-article:1813669 | pubmed:abstractText | Endothelin-1 (ET), a potent vasoconstrictor, induces a sustained increase in the phosphorylation level of the 20-kDa myosin light chain (MLC) in porcine coronary artery strips. ET also induces late phosphorylation of caldesmon, which is mimicked by 12-deoxyphorbol 13-isobutyrate, but not by 60 mM KCl. Nitroglycerin, a vasorelaxant, completely reverses the ET-induced phosphorylation of MLC, but not that of caldesmon. These results suggest an important regulatory role of MLC phosphorylation in ET-induced contraction. | lld:pubmed |