Endothelin-like immunoreactivity in the aqueous humour and in conditioned medium from cultured ciliary epithelial cells.
Endothelin-like immunoreactivity was detected in human (15.6 +/- 2.7 pg/ml) and bovine (11.1 +/- 0.98 pg/ml) aqueous humour of the eye. These concentrations are 2-3 times higher than the corresponding plasma levels. Cultured human nonpigmented ciliary epithelial cells released endothelin-like immunoreactivity with a maximum of 2.1 +/- 0.32 pg/(cm2* 48 h). The release was stimulated by fetal calf serum, thrombin, carbachol and phorbol ester and blocked by cycloheximide. Immunocytochemistry showed cytoplasmic staining of cultured human nonpigmented ciliary epithelial cells for endothelin-1. Endothelin-1 was shown to induce contractions in isolated human ciliary muscle by isometric force measurements. Endothelin in the aqueous humour may play a role in the regulation of intraocular pressure.
Lepple-Wienhues
A
A
Institut für Klinische Physiologie, Klinikum Steglitz, Freie Universität Berlin, Germany.
Becker
M
M
Stahl
F
F
Berweck
S
S
Hensen
J
J
Noske
W
W
Eichhorn
M
M
Wiederholt
M
M
D000818:Animals; D001082:Aqueous Humor / Q000737:chemistry*; D002217:Carbachol / Q000494:pharmacology; D002417:Cattle; D002478:Cells, Cultured; D002924:Ciliary Body / Q000737:chemistry* / Q000187:drug effects; D003470:Culture Media / Q000737:chemistry; D003513:Cycloheximide / Q000494:pharmacology; D016232:Endothelins / Q000032:analysis* / Q000494:pharmacology; D006801:Humans; D007124:Immunoenzyme Techniques; D007537:Isometric Contraction; D009132:Muscles / Q000187:drug effects / Q000502:physiology; D010703:Phorbol Esters / Q000494:pharmacology; D010857:Pigment Epithelium of Eye / Q000737:chemistry*
D003470:Culture Media; D016232:Endothelins; D010703:Phorbol Esters; D002217:Carbachol; D003513:Cycloheximide