ISSN:
1440-1681
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
1. Intravenous endothelin-1 releases endothelium-derived relaxing factor (EDRF) and prostacyclin from the lungs, and substantial pulmonary clearance is claimed. Since these vaso-active substances could alter the haemodynamic effects of endothelin-1, the effects of boluses of endothelin-1 injected intravenously and into the left ventricle (intra-arterial) were compared, measuring arterial pressure and heart rate in conscious male New Zealand rabbits. The pulmonary clearance of endothelin-1-like immunoreactivity (Et-1LI) and initial plasma half-life were measured in anaesthetized rabbits during and after intravenous infusion of endothelin-1.2. The effects of intravenous and intra-arterial routes of administration were not significantly different. Arterial pressure decreased (intravenous: 21.6, intra-arterial: 24.2 mmHg, P= 0.12, n= 10, t-test, 9 d.f.), then increased (intravenous: 21.2, intra-arterial: 16.4 mmHg, P= 0.33), while heart rate increased (intravenous: 66, intra-arterial: 53 beats/min, P = 0.09), then decreased (intravenous: 50, intra-arterial: 54 beats/min, P= 0.30).3. Arterial and venous plasma levels of Et-1LI were not significantly different, venous levels increasing from 30 ± 3 pg/ mL (12 ± 1 pmol/ L) at 1 pmol/ kg per min to 770 ± 78 pg/ mL (308 ± 31 pmol/L) at 16 pmol/kg per min (n = 5). Mean initial plasma half-life was 0.6 min (range: 0.25–1.1 min).4. It was concluded that there is no significant net pulmonary clearance of exogenously administered endothelin-1 in the conscious rabbit, and that any vaso-active factors released in the lungs by endothelin-1 do not have a significant effect on systemic arterial pressure.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1440-1681.1994.tb02521.x
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