Some Aspects of the Pharmacology of β-Adrenoreceptor Blockers
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- Åblad, B., Carlsson, E., Dahlöf, C. et al. Drugs (1976) 11(Suppl 1): 100. doi:10.2165/00003495-197600111-00025
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The pharmacodynamic properties of a β-blocker are mainly determined by its affinity to β1 andβ2-receptors respectively and by its intrinsic activity. It is suggested that there is no absolute organ separation of the two receptor sub-types. Instead bothβ1 andβ2 -receptors are involved in the mediation of the same effect. The frequency distribution ratio of β1/β2-receptors varies markedly among various effector responses.
A non-selective and aβ1-selective blocker may have different haemodynamic effects when the levels of circulating adrenaline are high, because of their markedly different potency in inhibiting theβ2-mediated vasodilator effect of adrenaline. Data are presented which suggest the existence of a presynapticβ1 -receptor mediating a positive feedback mechanism on neuronal release of noradrenaline.