Effect of prostaglandins F2? and E2 on sensitivity of rabbit cortical neurons to acetylcholine and noradrenalin

Abstract

The effect of prostaglandins F2α and E2 on unit activity and sensitivity of somatosensory cortical neurons of rabbits to acetylcholine and noradrenalin was investigated by microiontophoresis. Prostaglandin F2α predominantly inhibited, whereas E2 increased the spike activity of the neurons. F2α usually modified the sensitivity of the neurons to acetylcholine, E2 to noradrenalin. The influence of F2α on the excitatory effects of acetylcholine, and of E2 on the inhibitory effects of noradrenalin as a rule was characterized by weakening of the action of the mediators or a change in the sign of the initial responses. It is suggested that prostaglandins of the F group participate in cholinergic, and those of the E group in adrenergic transmission. The prostaglandins studied evidently exert their action through selective inhibition of the activity of adenylate or guanylate cyclases, leading to a decrease in the synthesis of secondary transmitters, namely cyclic AMP and cyclic GMP.