[Mechanisms of cutaneous-cardial interconnections]

Using the method of double stimuli, some features of inhibitory influences of conditioning stimulation of cutaneous zones on the afferent transmission from the heart were studied in the experiments on cats. It has been shown that when the interval between testing and conditioning stimuli is from 50 to 150 ms, the cutaneous stimulations effectively block the appearance of evoked potentials in the rostral parts of the cerebral cortex, which were induced by the electrical stimulation of the sinoatrial nodal zone. Bilateral vagotomy completely eliminated this reaction. Stimulation of the peripheral part of the cut vagus also effectively blocked the transmission of the afferent impulses from the heart. It was concluded that inhibitory cutaneo-cardiac effects are determined by the mechanisms of presynaptic inhibition, which develop at the level of intracardiac nervous system.