Analysis of vasocontractile responses to endothelin-1 in rabbit retinal vessels using an ETA receptor antagonist and an ETB receptor agonist

Life Sci. 1993;53(6):PL111-5. doi: 10.1016/0024-3205(93)90707-a.

Abstract

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dose-Response Relationship, Drug
  • Endothelin Receptor Antagonists*
  • Endothelins / antagonists & inhibitors
  • Endothelins / pharmacology*
  • Female
  • Male
  • Peptide Fragments / pharmacology
  • Peptides, Cyclic / pharmacology
  • Rabbits
  • Receptor, Endothelin A
  • Receptor, Endothelin B
  • Receptors, Endothelin / drug effects*
  • Retinal Artery / drug effects*
  • Retinal Artery / physiology
  • Vasoconstriction / drug effects*

Substances

  • Endothelin Receptor Antagonists
  • Endothelins
  • Peptide Fragments
  • Peptides, Cyclic
  • Receptor, Endothelin A
  • Receptor, Endothelin B
  • Receptors, Endothelin
  • BQ 3020
  • cyclo(Trp-Asp-Pro-Val-Leu)