Effects of the serotonin-antagonist ketanserin on the function of ischaemic and normally perfused myocardium and modification by β-1-blockade in anaesthetized normotensive dogs |
| |
Authors: | H Schad W Heimisch A Barankay S Hesse N Mendler |
| |
Institution: | 1. Klinik für Herz- und Gef?sschirurgie, Deutsches Herzzentrum München, Lothstrasse 11, W-8000, München 2, Federal Republic of Germany 2. Institut für An?sthesiologie, Deutsches Herzzentrum München, Lothstrasse 11, W-8000, München 2, Federal Republic of Germany
|
| |
Abstract: | The 5-HT-2 antagonist ketanserin (KAS) has been successfully used to treat acute hypertension in coronary bypass surgery.
The present study was performed to investigate the effect of KAS on ischaemic myocardium. In 11 anaesthetized (piritramide)
dogs, systolic contraction (sdL) and end-diastolic length (edL) of myocardium supplied by the left descending coronary artery
(LAD) and the left circumflex coronary artery (LCX) were measured by sonomicrometry simultaneously with aortic pressure (AoP),
left ventricular dP/dtmax and end-diastolic pressure (LVedP), heart rate (HR), stroke volume, and LAD flow (QLAD). Regional
ischaemia to decrease sdLLAD (−48%) was achieved by LAD stenosis (QLAD −47%). Concomitantly, edLLAD increased by 8%. However,
the other variables did not change. Then KAS was given i.v. (0.15+ 0.15+0.30+0.6mg/kg) at 15-min intervals. Following KAS,
prestenotic sdLLAD recovered in a dose-dependent manner. LVedP and edLLAD decreased, sdLLCX increased, and the other variables
were not affected. This functional recovery of ischaemic myocardium was attenuated by pretreatment with metoprolol (MET, 1
mg/kg) prior to LAD stenosis. The ischaemic area was not irreversibly damaged, however, as proven by the recovery of prestenotic
sdLLAD values after release of the stenosis. The improved systolic shortening of ischaemic myocardium following KAS did not
result from restored QLAD due to post-stenotic vasodilation or break up of platelet aggregates (QLAD did not increase) or
from reduced afterload (AoP did not decrease). Obviously, it was mediated by β-1-receptors, as shown by the attenuation of
the beneficial effect of KAS by pretreatment with MET. |
| |
Keywords: | Ketanserin Metoprolol Ischaemic myocardium Anaesthetized dogs |
本文献已被 SpringerLink 等数据库收录! |
|