Effect of intracisternal butoxamine, a beta-2 adrenoceptor blocking agent, on blood pressure and heart rate in the dog.

The cardiovascular effects of intracisternally administered butoxamine, a beta 2-adrenoceptor blocking drug, were studied in both normotensive and acute hypertensive anaesthetized dogs. Acute hypertension was elicited by sino-aortic denervation (deafferentation). Intracisternal butoxamine (25-400 microgram/kg) failed to decrease blood pressure and reduce heart rate in the two groups of animals. These results show that the decrease in blood pressure elicited by central administration of dl-propranolol is probably not related to central beta 2-adrenoceptor blockade.