Effects of pentazocine on coronary hemodynamics under pentobarbital or chloralose-urethane anesthesia in dogs.

The effect of pentazocine on the coronary hemodynamics was studied in anesthetized dogs. Under pentobarbital anesthesia pentazocine did not cause any significant changes in the coronary hemodynamics. Under chloralose-urethane anesthesia, however, it produced a statistically significant increase in heart rate, left coronary blood flow rate, myocardial oxygen consumption as well as myocardial oxygen extraction rate, but a decrease in coronary vascular resistance. These results indicate that the effects of pentazocine on the coronary hemodynamics are modified significantly by the drugs used for basal anesthesia.