RESUMO
As is known, the pineal gland plays an important role in adaptogenesis, and the hypothalamus is one of the main links of the stress-reactive system and is involved in the regulation of the involution of the whole organism. So, the study of changes in these organs during stress and aging is very interesting. The aim of the work is to study the mechanisms of apoptosis of pinealocytes and neurosecretory cells of the suprachiasmatic nucleus of the hypothalamus during aging, stress, and under the conditions of pharmacological correction of involutional processes and stress response (antioxidant alpha-tocopherol acetate, immunomodulator cycloferon). We used Wistar rats as model, young (2-4 months) and old (30 months). Age-related features of the apoptosis dynamics of pinealocytes and neurosecretory cells of the hypothalamic suprachiasmatic nucleus were studied using TUNEL and immunohistochemistry, and the possibilities of pharmacological correction of apoptotic processes are determined. An age-dependent increase of apoptosis level of cells of suprachiasmatic nucleus and epiphysis in rats was revealed. The stress effect (immobilization) led to the intensification of cell death, more significant in older animals. The pineal gland and suprachiasmatic nucleus, traditionally regarded as regulators of circadian rhythms, are at the same time actively involved in general adaptation processes. The studied drugs (α-tocopherol-acetate, cycloferon, and their combination) have a pronounced anti-apoptotic, cytoprotective effect under physiological conditions during aging, as well as during non-specific emotional stress (immobilization) in young and old animals. The regulatory effect is accomplished by activating the expression of the anti-apoptotic protein Bcl-2 in the neurosecretory cells of the suprachiasmatic nucleus and pinealocytes.