Transmural triglycerides in acute myocardial ischaemia.

The effect of coronary artery occlusion on endogenous triglycerides of left ventricular subepicardium and subendocardium was studied in the open-chest anaesthetised dog. Under control conditions, the subepicardium was found to have a greater concentration of triglycerides than the subendocardium. Thirty minutes after acute coronary artery occlusion there was a decrease followed by a steady increase at 60, 120, and 240 min in subepicardial triglycerides of the ischaemic region. No change in triglycerides in the subendocardium of normal or ischaemic regions was observed. The initial decrease of subepicardial triglycerides in the ischaemic region was blocked by administration of propranolol or bevantolol (CI-775; a specific beta 1 antagonist) given 30 min before occlusion. It is concluded that the effect of coronary artery ligation on transmural endogenous triglycerides is biphasic with an initial period of increased mobilisation followed by a period of increased deposition.