Some New Adrenergic Neurone Blocking Agents

INTERFERENCE with the release of the adrenergic transmitter, noradrenaline, by chemical blockade of post-ganglionic adrenergic neurones has become anaccepted tool in the management of the hypertensive state 1 . The chemical structures involved 2 indicate that the presence of a cationic head with strong basicity, such as quaternary ammonium or guanidine 3 , is required for adrenergic neurone-blocking property, imparting a high degree of ionization to the molecule. The molecular mechanism of this type of drug interference is unknown. Failure of nerve impulse transmission, however, might occur by hyper-polarization or by depolarization of the terminal nerve membrane, initiated by the charge-carrying molecules. Significant inhibition of the biosynthesis of the transmitter by the foregoing compounds can be excluded as a possible mode of action on account of more recent work 4 .