J Cardiovasc Pharmacol
December 1988
Clonidine-induced coronary vasodilation was studied in anesthetized dogs pretreated with propranolol to achieve beta-adrenoceptor blockade. The left circumflex coronary artery (LCX) was perfused with arterial blood from a reservoir maintained under a constant pressure of 100 mm Hg. Clonidine when administered directly into the coronary vascular bed in doses of 30, 100, and 300 micrograms induced a dose dependent coronary vasodilation, which was inhibited by cimetidine, but not by idazoxan, methysergide, methylscopolamine, yohimbine, diphenhydramine, ketanserin, or theophylline.
View Article and Find Full Text PDFRecent Adv Stud Cardiac Struct Metab
February 1978
1. The effect of intravenous pentaerythritol trinitrate and glyceryl trinitrate on left ventricular subepicardial (epi) and subendocardial (endo) PO2 and perfusion were compared in anaesthetized open-chest mongrel dogs. Tissue PO2 was determined simultaneously at a depth of 3 mm (epicardial) and 9 mm (endocardial) with small platinum electrodes by polarography.
View Article and Find Full Text PDFClin Exp Pharmacol Physiol
September 1978
1. The effects of pentaerythritol trinitrate (pentrinitrol) and glyceryl trinitrate on myocardial oxygen consumption and myocardial and systemic haemodynamics were studied in anaesthetized open-chest dogs. An in vivo oximeter in the coronary sinus permitted continuous determination of arteriovenous oxygen difference and myocardial oxygen consumption.
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