Beta 1-selective and non-selective beta-adrenoceptor blockade, anaerobic threshold and respiratory gas exchange during exercise.

Anaerobic threshold and respiratory gas exchange during exercise.

The effect of oral doses of the beta 1-selective adrenoceptor antagonist atenolol (50 mg), the non-selective antagonist propranolol (40 mg) and placebo was investigated during exercise in a crossover comparison in six healthy but untrained subjects. Descriptors of ventilation, respiratory gas exchange, and arterialized blood lactate and glucose were obtained during steady state bicycle ergometr...

Selective beta 1 and beta 2 adrenoceptor blockade on epinephrine-induced arrhythmias in halothane anaesthetized dogs.

Beta 2 as well as beta 1 adrenoceptors have been recognized in the heart of vertebrates. They mediate a positive chronotropic action of catecholamines. We compared the effect of selective beta 1 and beta 2 adrenoceptor antagonists on the genesis of halothane-epinephrine arrhythmias in dogs. The arrhythmogenic dose (AD) of epinephrine was increased in the presence of l-metoprolol, a selective be...

Selective and Nonselective Beta-adrenoceptor Blockade in Hypertension: Responses

The hypertensive response to the infusion of epinephrine is exaggerated in subjects treated with noncardioselective ,B-adrenergic antagonists, but not in subjects given cardioselective agents. In this study, we sought to determine whether the same holds true when hypertensive patients treated with these drugs are subjected to acute physiologic stress. According to a randomized crossover protoco...

Selective and nonselective beta-adrenoceptor blockade in hypertension: responses to changes in posture, cold and exercise.

Beta-adrenoceptor blockade and anesthesia

A potential for impaired cardiovascular performance among anesthetized patients due to preoperative treatment with propranolol was considered based on clinical observation of sudden, irretractable cardiac failure in five patients. As a result, a recommendation to terminate beta-adrenoceptor therapy prior to general anesthesia was advanced. During the ensuing decade many clinical researchers sou...