Abstract
Pulmonary vascular responses to endothelin-2 and sarafotoxin 6b were investigated in the feline pulmonary vascular bed under natural flow and constant flow conditions. Injections of endothelin-2 and sarafotoxin 6b in a dose of 0.3 nmol/kg iv increased pulmonary arterial and left atrial pressures and cardiac output, and caused a biphasic change in calculated pulmonary vascular resistance. Endothelin-2 caused a biphasic change in systemic arterial pressure, while sarafotoxin 6b only decreased arterial pressure. Under constant flow conditions in the intact-chest cat, injections of endothelin-2 and sarafotoxin 6b in doses of 0.1-1 nmol into the perfused lobar artery increased lobar arterial pressure in a dose-related manner but were less potent than the thromboxane A2 mimic, U46619. An ET analog with only the Cys1-Cys15 disulfide bond and an amidated carboxy terminus had no significant activity in the pulmonary vascular bed. The present data show that endothelin-2 and sarafotoxin 6b have significant vasoconstrictor activity in the pulmonary vascular bed of the cat.
Original language | English (US) |
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Pages (from-to) | 211-214 |
Number of pages | 4 |
Journal | Canadian Journal of Physiology and Pharmacology |
Volume | 69 |
Issue number | 2 |
DOIs | |
State | Published - 1991 |
Externally published | Yes |
Keywords
- Endothelin-2
- Pulmonary circulation
- Sarafotoxin 6b
ASJC Scopus subject areas
- Physiology
- Pharmacology
- Physiology (medical)