MORPHOLOGICAL CHANGES IN THE BRAIN AND ADRENAL GLANDS UNDER CHRONIC IMMOBILIZATION STRESS AND THEIR CORRECTION WITH MELATONIN

Authors:

Abstract:

The purpose of the study was to determine morphological changes in the brains and adrenal glands of rats under chronic immobilization stress and to evaluate these changes under melatonin administration. Fifteen sexually mature male Wistar rats were divided into three groups (n=5): control, chronic immobilization stress, and chronic immobilization stress with melatonin (5 mg/kg orally for 21 days). Serum cortisol concentration was measured by immunochemiluminescence; brain and adrenal samples were examined after hematoxylin and eosin staining. Immobilization stress was accompanied by an increase in cortisol levels from 1.66±0.20 to 13.80±0.33 nmol/L (p<0.05), vascular engorgement, erythrocyte stasis or aggregation, and expansion of perivascular and pericellular spaces in the brain. In the melatonin group, cortisol levels were 11.04±0.28 nmol/L, 20% lower than in the uncorrected stress group (p<0.05); the microcirculatory and tissue changes described were less pronounced. The adrenal architecture remained intact; however, vascular and cytoplasmic changes differed between groups. The data indicate a partial protective effect of melatonin under chronic immobilization stress; confirmation requires quantitative morphometry, corticosterone measurement, and molecular markers of neuroinflammation and autophagy.

Keywords:

chronic immobilization stress melatonin brain adrenal glands morphology neuroprotection

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Publication:

«World of Medicine and Biology» Vol. 22 No. 97 (2026), pp. 172-175
UDC [616.8-009.63:616.45-092]:[612.018.1]:[001.891]

DOI:

https://doi.org/10.26724/2079-8334-2026-3-97-172-175