Endothelin-mediated Intracellular Calcium Mobilization in Cultured Bovine Corneal Endothelium.

Hahn, Tae Won; Cha, Seok Ho; Lee, Keon Haong; Kim, Jae Ho

Original Article

Journal of the Korean Ophthalmological Society 1999;40(1):31-39.
Published online January 1, 1999.

Endothelin-mediated Intracellular Calcium Mobilization in Cultured Bovine Corneal Endothelium.

Tae Won Hahn, Seok Ho Cha, Keon Haong Lee, Jae Ho Kim

¹Department of Ophthalmology,College of Medicine,The Catholic University of Korea, Korea.
²Department of Pharmacology,College of Medicine,The Catholic University of Korea, Korea.

배양된 소 각막내피세포에서 Endothelin 수용기 매개에 의한 세포내 유리 칼슘의 변화

한태원(Tae Won Hahn) , 차석호 , 이권행 , 김재호

Abstract

To investigate the effect of endothelin on intracellular free calcium ([Ca(2+)]i) mobilization and the existence of the endothelin receptor in cultured bovine corneal endothelial cells(BCEC), endothelin-1(ET-1) -induced [Ca(2+)]i increase was measuredby using calcium sensitive indicator, fura-2/AM, and the studies on its desensitizaton and receptor antagonists were also performed. ET-1 increased [Ca(2+)]i in a concentration-dependent manner(10(-9)M-10(-5)M) and ET-1 -unduced [Ca(2+)]i transient increase was significantly ingibited (~50%) by the pretreatment with EGTA for 1 min. Similarly, neomycin also attenuated ET-1 -unduced [Ca(2+)]i transient increase in a concentration-dependent mannet. Desensitizatin study with successive treatment of ET-1 and ET-3, and the experiments of antagonists(BQ-610 for the ET(A) receptor and BQ-788 for the ET(B) receptor) showed the presence of ET(B) receptor in BCEC. In addition, ET-1(10(-6)M) accumulated inositol trisphosphate about two folds (310+/-6.8 cpm) comparing to control(154+/-11.6 cpm) and this accumulation was significantly inhibited by the treatment with neomycin (187+/-28 cpm). These results suggest that endothelin-induced calcium mobilization is receptor-mediated response and TE(B) receptor exists in BCEC.

Key Words: Bovine corneal endothelial cells;Endothelin;Intracellular Calcium