Stress-induced changes in the state of the paraventricular nucleus of the rat hypothalamus.

Abstract

At present, the study of the place and role of neuroendocrine structures in the central mechanisms of circadian rhythms is one of the pressing issues of modem chronophysiology. Changes in the duration of the main time setter - the photoperiod, as a stress factor, desynchronize the rhythms of somatic and visceral functions, as well as the coordination and modulation of the mechanisms of adaptation of the organism to the influence of various factors. One of the structures that are primarily involved in the neuroendocrine response to stress reactions is the subnucleus of the paraventricular nucleus (PVN) of the hypothalamus. There is no information in the literature on the morpho-functional characteristics of PVN for different photoperiod durations. The aim of the study. The study aims to determine the effect of photoperiod modifications on the morphofunctional state of the PVN subnuclei at different times of the day.