Acute Cardiovascular Effects of Dichloroallyl Lawsone (NSC-126771) Following Single Bolus Intravenous Injections to Anesthetized Beaglehounds.

摘要

Effects of Dichloroallyl lawsone on ECG,vascular pressures and resistances,cardiac output,left ventricular contractility,and arterial blood gases were studied on healthy beaglehounds anesthetized with Innovar-pentobarbital. Single intravenous bolus injections of placebo,and boluses of approximately 32, 16, 8, 4or 2mg Dichloroallyl lawsone/kg body weight were given. Records were obtained during 2pretest periods,and at 5, 20, 40,and 60minutes post injection. Dogs receiving 32mg/kg,and to lesser extents dogs receiving 16mg/kg,developed within 5minutes:tachycardia, tachypnea,increase in pulmonary and systemic vascular pressures and resistances,and decrease in partial pressure of CO2. Abbreviation of QT interval was probably a sequel to the tachycardia;while decrease in PaCO2resulted,probably,from hyperventilation. These changes may result from a direct effect of Dichloroallyl lawsone on medullary cardio-vaso-respiratory centers.