[Effect of "blue spot" hyperactivation on the rhythm of the intact heart and the heart with altered reactivity].

Experiments on rats were made to study the character of rhythmical activity of intact heart and heart with abnormal reactivity under electrical stimulation of the blue spot (BS) and formation in it of the generator of pathologically enhanced excitation (GPEE) by penicillin microinjections. Hyperactivation of the BS by electrostimulation or formation of the GPEE led to the same disorders of rhythmical activity. Provoking changes in intact heart rhythm according to the tachycardia type, hyperactivation of the BS was accompanied by various arrhythmias under abnormalities of the heart regulatory mechanisms proper. It is assumed that hyperactivation of the BS may initiate cardiac rhythm disturbances. The dependence of the realization of pathological process on the changes in control apparatus function and target organ reactivity is stressed.