Adrenoceptors--classification, activation and blockade by drugs.

The interaction between drug and receptor evokes a series of reactions resulting in a physiological response. A recognition site, an amplifier system and an effector system are involved in the mediation of effect. A brief review is given of the historical development of the adrenoceptor concept, of the classification of adrenoceptors, and of the consequences of stimulation and blockade of these receptors by drugs.