Cellular mechanism of thrombin on endothelin-1 biosynthesis and release in bovine endothelial cell

• Published in: Biochemical pharmacology Vol. 44; no. 12; p. 2409
• Main Authors: Emori, T, Hirata, Y, Imai, T, Ohta, K, Kanno, K, Eguchi, S, Marumo, F
• Format: Journal Article
• Language: English
• Published: England 15.12.1992
• Subjects: Animals; Calcium - metabolism; Cattle; Cells, Cultured; Dose-Response Relationship, Drug; Endothelin-1; Endothelins - biosynthesis; Endothelins - metabolism; Endothelium - metabolism; Gene Expression Regulation; Inositol 1,4,5-Trisphosphate - biosynthesis; Pipecolic Acids - pharmacology; Protein Precursors - metabolism; RNA, Messenger - metabolism; Thrombin - antagonists & inhibitors; Thrombin - pharmacology
• ISSN: 0006-2952
• DOI: 10.1016/0006-2952(92)90687-e

We have studied the cellular mechanism responsible for induction of preproendothelin (preproET)-1 mRNA and release of ET-1 by thrombin in cultured bovine endothelial cells (ECs). Thrombin induced an immediate and dose-dependent formation of inositol-1,4,5-trisphosphate (IP3) with a concomitant increase in intracellular Ca2+ concentration ([Ca2+]i). The thrombin-induced ET-1 release was abolished either by a phospholipase C inhibitor, a protein kinase C (PKC) inhibitor, or an intracellular Ca(2+)-chelator, whereas a Ca(2+)-channel antagonist was ineffective. A selective thrombin inhibitor (argatroban) decreased IP3 formation and the increase in [Ca2+]i and ET-1 release stimulated by thrombin. Northern blot analysis revealed that thrombin-induced expression of preproET-1 mRNA was inhibited completely by a PKC inhibitor and partially by argatroban. These data suggest that thrombin is involved in the mechanism of preproET-1 mRNA expression and subsequent ET-1 release, possibly through activation PKC and mobilization of intracellular Ca2+ resulting from the receptor-mediated phosphoinositide breakdown in ECs.