[Modulating effect of angiotensin II and bradykinin on the mediator sensitivity of central neurons]

Using the methods of extracellular recording of bioelectrical activity and microiontophoresis, the effect of endogenous neuropeptides (angiotensin-II and bradykinin) on the cortical neuronal sensitivity to neurotransmitters was investigated in conscious rabbits. It was found that angiotensin-II and bradykinin modified neuronal responses to neurotransmitters, increasing, decreasing and reversing their mediator sensitivity. The most prominent effect of these neuropeptides was the increase of neuronal responses to acetylcholine and noradrenaline. At the central neuronal level, endogenous neuropeptides (angiotensin-II and bradykinin) are suggested to play the role of synaptic polytransmitter neuromodulators.