Analysis of the relationship between the activity of the reticular formation of the medulla oblongata, respiratory and cardiovascular systems in rats under painful stimulation

Abstract

Using the method for calculating the average of conditional probabilities of recurrence intervals, a comparative analysis was performed to estimate the direction of coupling between different physiological rhythms in the form of fluctuations in blood pressure, respiration, and the activity of neurons in the reticular formation of the medulla oblongata in two groups of anesthetized rats under pain stimulation or no stimulus. It was found that there are different kinds of the directions of coupling between the analyzed rhythms. Most of the data obtained for rats from the control group and rats with experimentally induced colitis suggest the statistically significant unidirectionality of coupling. Painful stimulation did not affect the direction of coupling, but the amount of data on unidirectionaity of coupling slightly reduced. At the same time, the rhythms associated with the cardiovascular system (blood pressure variability) were controlled by the rhythms of the respiratory system, and the respiratory rhythm controlled the variability of the activity of neurons in the reticular formation of the medulla oblongata.