Pshychenko V. Changes in morphological and functional state of the pineal gland of rats under different types of stress

The thesis is devoted to the study of morphological and functional state of the pineal gland in acute and chronic stress on the background of changed photoperiod. On the basis of histological and morphometric studies found that morphological and functional changes in the pineal gland under the influence of stress factors are less pronounced in animals which simulated physiological hyperfunction of pineal gland. In animals subjected to stress on the background of the pineal gland hypofunction found more pronounced morphological changes in the parenchyma of the organ and vascular bed. Experimentally proved, increased functional activity of the pineal gland in rats acute stress and acute stress on the physiological background of the pineal gland hyperfunction. The increase of the amount of light pinealocytes and increase their morphometric parameters. From the vascular system revealed signs of arterial hyperemia. In the rat pineal gland hypofunction of acute stress is accompanied by changes of opposite character: the number of active cells reduced light and dark, contrast is increased. Lowering of morphometric parameters of light pinealocytes, and violation of rheological properties of blood, indicating that the inhibition of the functional activity of the pineal gland. It is proved that chronic stress combined with hyper- and hypofunction pineal gland leads to inhibition of the functional activity of the pineal gland. We found a significant decrease in the amount of light cells, a significant decrease in their morphometric parameters and the lack of blood cells in the lumen of blood vessels.