Central nervous actions of /7-adrenoreceptor antagonists

Since the introduction of the /?-adrenoreceptor antagonists to clinical practice in the late 1960s, their use has become established in a variety of cardiovascular diseases in which their mode of action depends upon the attenuation of effects of sympathetic stimulation. In hypertension, how­ ever, the mode of action is uncertain and a centrally mediated action has been proposed. Furthermore a beneficial effect in disorders of the central nervous system has been suggested but not proven. In the last 2 years, the presence of ßadrenoreceptors in the central nervous system has been convincingly demonstrated and this has provided an approach to the rational use of these drugs in central nervous system dysfunction. We intend briefly to present the evidence that there are /J-adrenoreceptors in the central nervous system, that the /?-adrenoreceptor antagonists have central effects in animals and man and that these may be responsible for some of their therapeutic effects. Caution must, however, be exercised in making this interpretation from the available evidence since we also draw attention to the hitherto unexpected finding that many /8-adrenoreceptor antagonists also affect responses to 5-hydroxytryptamine and bind specifically to its receptor in central nervous system tissues.