title: Endostatin inhibits T-type Ca2+ channel current in guinea pig ventricular myocyte.
abstract: Endostatin, a fragment of collagen XVIII, is known as an endogenous angiogenesis inhibitor, and its serum concentration increases in various cardiovascular diseases. T-type Ca(2+) channel, low voltage-activated Ca(2+) channel, is not expressed in adult ventricular myocytes. Re-expression of T-type Ca(2+) channels in cardiac myocytes is thought to be involved in the development of cardiac hypertrophy. We examined the effects of endostatin on T-type Ca(2+) channel current by whole-cell patch clamp technique in freshly isolated adult guinea pig ventricular myocytes, which exceptionally express T-type Ca(2+) channels. Although endostatin 300 ng/ml had no effect on L-type Ca(2+) current, it significantly inhibited T-type Ca(2+) current. These data indicate that endostatin can be an endogenous inhibitor of T-type Ca(2+) channels in the cardiac myocytes.
authors.affiliation: Laboratory of Veterinary Pharmacology, School of Veterinary Medicine, Kitasato University, Higashi 23 bancho 35-1, Towada-shi, Aomori 034-8628, Japan.
authors.forename: Jumpei
authors.initials: J
authors.lastname: Yasuda
authors.forename: Muneyoshi
authors.initials: M
authors.lastname: Okada
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Yamawaki
mesh_terms: D020533:Angiogenesis Inhibitors / Q000494:pharmacology; D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D020747:Calcium Channels, T-Type / Q000378:metabolism*; D020013:Calcium Signaling; D043169:Endostatins / Q000494:pharmacology*; D006168:Guinea Pigs; D006352:Heart Ventricles / Q000166:cytology*; D032383:Myocytes, Cardiac / Q000378:metabolism*
chemical_list: D020533:Angiogenesis Inhibitors; D002121:Calcium Channel Blockers; D020747:Calcium Channels, T-Type; D043169:Endostatins