[Endothelin-1-induced vasoconstriction in retinal blood vessels in the rabbit].
Endothelin-1 (ET-1) is an endothelium-derived potent vasoconstrictor peptide which is synthesized in retinal vessels. In order to investigate its effect on retinal blood vessels, we injected ET-1 intravitreally (10(-12), 3 x 10(-12), 10(-11), 3 x 10(-11), 10(-10) mole) and examined the change in diameters of retinal arteries in rabbits by fundus photography. After injection of a high dose (10(-10) mole) of ET-1, fluorescein angiography was used to investigate whether complete occlusions of retinal blood vessels occurred or not. 3 x 10(-12) mole ET-1 induced contraction of retinal arteries and the contraction of those induced by 10(-10) mole ET-1 showed complete occlusion. A medium dose (10(-11) mole) of ET-1 caused repeated vasospasms and segmental vasoconstrictions of retinal blood vessels. Fluorescein angiograms revealed that retinal blood flow was interrupted transiently by injection of a high dose (10(-10) mole) of ET-1. These findings suggested that intravitreal injection of ET-1 could provide a new model of experimental transient occlusion of retinal vessels in rabbits.
Sato
T
T
Department of Ophthalmology, University Hospital of Tsukuba, Japan.
Takei
K
K
Nonoyama
T
T
Miyauchi
T
T
Goto
K
K
Hommura
S
S
D000818:Animals; D016232:Endothelins / Q000494:pharmacology*; D005260:Female; D005451:Fluorescein Angiography; D008297:Male; D011817:Rabbits; D012171:Retinal Vessels / Q000187:drug effects*; D014662:Vasoconstrictor Agents / Q000494:pharmacology*
D016232:Endothelins; D014662:Vasoconstrictor Agents