Blockade by SKF 525A of the rat sympathetic ganglia and the adrenal medulla.

SKF 525A (1.5-9 mg/kg), depending on the dose used, reduced or abolished the hypertensive effect of McN-A-343, DMPP and nicotine, but did neither noticeably affect the hypertensive effect of tyramine, adrenaline and noradrenaline, nor the hypotensive effect of acetylcholine and orciprenaline. It is concluded that SKF 525A blocks the rat sympathetic ganglia and the adrenal medulla. This blockade is non-specific. It is suggested that the blockade results from the stabilizing effect of SKF 525A on postsynaptic membranes of the sympathetic ganglia and the adrenal medulla.