The cellular mechanism of action by vasoconstrictor hormones in cultured rat vascular smooth muscle cells.
The effects of angiotensin (Ang) II, arginine vasopressin (AVP), and serotonin (5-HT) on inositol trisphosphate (IP3) production, cytosolic Ca2+ concentration [( Ca2+]i), and the phosphorylation of 20 kilodalton myosin light chain (MLC) were examined in cultured rat vascular smooth muscle cells (VSMC). These vasoconstrictors immediately induced dose-dependent and concomitant increases in IP3 production, [Ca2+]i, and phosphorylation of 20 kDa MLC. The agonist-induced increases in IP3 production, [Ca2+]i, and phosphorylation of 20 kDa MLC in VSMC were completely blocked by pretreatment with the receptor antagonists for Ang II, V1, and 5-HT2, respectively. These data suggest that receptor-mediated increases in IP3 production, [Ca2+]i, and phosphorylation of 20 kDa MLC by these vasoconstrictors are closely interrelated.
Takata
S
S
Department of Medicine, Kobe University School of Medicine, Japan.
Hirata
Y
Y
Takagi
Y
Y
Fukase
M
M
Fujita
T
T
D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D001127:Arginine Vasopressin / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D015544:Inositol 1,4,5-Trisphosphate / Q000096:biosynthesis; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000378:metabolism; D009218:Myosins / Q000378:metabolism; D010766:Phosphorylation; D051381:Rats; D012701:Serotonin / Q000494:pharmacology; D014662:Vasoconstrictor Agents / Q000494:pharmacology*
D014662:Vasoconstrictor Agents; D000804:Angiotensin II; D001127:Arginine Vasopressin; D012701:Serotonin; D015544:Inositol 1,4,5-Trisphosphate; D009218:Myosins; D002118:Calcium