Endothelin does not interact with angiotensin II in the coronary vascular bed of anesthetized dogs

P. Kiss, I. Horváth, I. Szokodi, P. Tóth, V. Kékesi, A. Juhász-Nagy, M. Tóth

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

We postulated that individually subthreshold circulating levels of angiotension II (Ang II) and endothelin-1 (ET-1) might induce fulminant coronary vasoconstriction when both are present. In 16 pentobarbital-anesthetized, open-chest mongrel dogs, blood pressure, heart rate, and standard ECG were registered continuously. Coronary blood flow (CBF) was measured in the left anterior descending coronary artery (LAD) by an electromagnetic flow probe. Drugs were administered into the LAD via an indwelling catheter. Bolus injections of Ang II (7.8 × 10-13 to 3.9 × 10-11 M) and ET-1 (10-12 to 10-9 M) induced a dose-dependent decrease in CBF (ΔCBFmax -82 ± 10% for Ang II and -91 ± 8% for ET-1). Simultaneous Ang II and ET-1 boluses had slightly smaller effects on CBF than the calculated additive figure. Five-minute infusions of Ang II (10-12 to 10-10 M/min) and ET-1 (5 × 10-12 to 2 × 10-10 M/min) induced a slight decrease in CBF (ΔCBFmax -12 ± 9% for Ang II and -19 ± 9% for ET). Background ET-1 or Ang II infusions did not alter the dose-response curve of the other drug. Simultaneous Ang II and ET-1 infusions at different rates (10-12 to 10-10 M/min for Ang II and 5 × 10-12 to 2 × 10-10 M/mm for ET-1) over 5 min had similar effects on CBF as the calculated additive figure (ΔCBFmax -35 ± 17% for the joint administration of the highest doses). We conclude that after simultaneous administration into the dog coronary artery, Ang II and ET-1 do not interact sufficiently to induce fulminant vasoconstriction.

Original languageEnglish
Pages (from-to)S103-S105
JournalJournal of cardiovascular pharmacology
Volume31
Issue numberSUPPL. 1
DOIs
Publication statusPublished - Jan 1 1998

Keywords

  • Angiotension II
  • Coronary circulation
  • Endothelin-1

ASJC Scopus subject areas

  • Pharmacology
  • Cardiology and Cardiovascular Medicine

Fingerprint Dive into the research topics of 'Endothelin does not interact with angiotensin II in the coronary vascular bed of anesthetized dogs'. Together they form a unique fingerprint.

  • Cite this