Effects of riboflavin tetra butyrate on the high energy phosphates in canine ischemic myo cardium
Nagatomo, T.; Satoh, H.; Sugai, T.; Etoh, Y.; Ushijima, T.; Sakurai, H.; Imai, S.
Acta Medica et Biologica 29(2): 135-145
Effects of riboflavin tetrabutyrate (RBF) on cardiohemodynamics and myocardial energy metabolism in epi- and endocardium during ischemic periods were studied in anesthetized mongrel dogs of either sex weighing 8-15 kg. RBF was injected 3 or 10 mg/kg daily for 1 wk. A mixture of propylene glycol and benzyl alcohol was used as a solvent. Ischemia was induced by ligating the anterior descending branch of the left coronary artery, which resulted in an increase in the heart rate associated with a slight fall of blood pressure. RBF produced an attenuation of the heart rate increase with a decline in blood pressure. Left ventricular pressure declined and left ventricular dp/dtmax [maximum charge in pressure with time] was decreased. RBF suppressed the reduction of energy rich phosphate compounds of the ventricular myocardium induced by ischemia. Concomitant with those changes was a tendency for lactate accumulation to be reduced in the ischemic heart muscle with redox potential becoming more positive. Evidently, RBF protected the canine heart from ischemic derangements through improvement of the energy metabolism and/or beneficial hemodynamic effects.