Takei K, Sato T, Nonoyama T, Hommura S, Miyauchi T, Goto K
Department of Ophthalmology, University of Tsukuba, Ibaraki, Japan.
Life Sci. 1993;53(6):PL111-5. doi: 10.1016/0024-3205(93)90707-a.
To study the role of endothelin receptor subtypes in rabbit retinal arteries, endothelin-1 (ET-1)-induced vasoconstriction was analyzed using the ETA receptor antagonist BQ-123 and the ETB receptor agonist BQ-3020. A cumulative injection of ET-1 (1 approximately 100 pmole) into the posterior vitreous body in anesthetized rabbits caused dose-dependent vasoconstriction in the retinal arteries, and ultimately caused complete obstruction. Fifteen minutes after BQ-123 (1 mumole) was injected into the posterior vitreous body, the dose-response curve of ET-1 was significantly shifted to the right. Intravitreal injection of BQ-3020 caused a significant retinal vasoconstriction only at the highest dose (1000 pmole). Therefore, in rabbit retinal arteries, ET-1-induced vasoconstriction appears to be mediated mainly through ETA receptors.
为研究内皮素受体亚型在兔视网膜动脉中的作用，使用ETA受体拮抗剂BQ - 123和ETB受体激动剂BQ - 3020分析内皮素 - 1（ET - 1）诱导的血管收缩。在麻醉兔的玻璃体腔中累积注射ET - 1（1至100皮摩尔）可导致视网膜动脉出现剂量依赖性血管收缩，并最终导致完全阻塞。在向玻璃体腔注射BQ - 123（1微摩尔）15分钟后，ET - 1的剂量反应曲线显著右移。玻璃体腔内注射BQ - 3020仅在最高剂量（1000皮摩尔）时引起显著的视网膜血管收缩。因此，在兔视网膜动脉中，ET - 1诱导的血管收缩似乎主要通过ETA受体介导。
