To (ss) block or better block?

BMJ 1995;311:701-702 (16 September)

Editorials

To (ß) block or better block?

ß1 selectivity rarely matters in clinical practice despitethe hype

Scarcely a week now passes without a new receptor subtype beingdescribed on which either endogenous neurotransmitters or hormonesmight act, usually as agonists, and which are rapidly proposedas novel targets for drugs, usually as antagonists. It is thereforeironic, but instructive, to recognise the debate that stillstirs among doctors and pharmacologists over the relative meritsof ß1 selective and non-selective ß blockade aftermore than 20 years' use in angina and hypertension.

The most recent airing of the debate concerned the paradoxicalpressor response to non-selective ß blockade.¹ ² In theabsence of ß blockade, acute rises in circulating adrenalineconcentrations hardly affect mean blood pressure because ofopposing actions on systolic and diastolic blood pressure. Therise in systolic blood pressure is due mainly to vasoconstrictionmediated by ( {alpha} ) adrenoceptors, and this is unopposed . . . [Full text of this article]