Abstract

INVESTIGATION OF CORTISOL PATTERN OXIDATIVE STRESS MARKERS’ ACTIVITY IN ANXIETY/DEPRESSIVE STATES OF STRESS-EVOKED WISTAR RATS

Ifedi Izuchukwu C., Chuemere A. N. and Olorunfemi O. J.*

ABSTRACT

Disruption in cognitive status as a result of assaults inundating the organisms have resulted in the aggravation of stress level leading to an appreciable magnitude of mental deficiency in animal. This work aimed at evaluating the level of cortisol in stress-evoked Male Wistar rats. Hundred and fifty Male rats of about three-month old (180-200 g) were used for this study. The rats were grouped into A (control- normal rats, rats without any drugs or shock), B (rats injected celebrex drugs and left to stay for one week, seven weeks and fourteen weeks (acute, subchronic and chronic levels), C (rats given ear shock/foot shock and left to stay for one week, seven weeks and forteen weeks), D (rats given retro-inversion/head-down maneuver shock and left to stay for one week, seven weeks and fourteen weeks), E (rats given tail immersion/tail clip shock and left to stay for one week, seven weeks and fourteen weeks) and F (rats given mechanical shock and left to stay for one week, seven weeks and fourteen weeks). The celebrex drugs used were injected to the rats at 0.1 mg/kg bw. Cortisol and antioxidant status were determined using enzyme-linked immunosorbent assay (ELISA) kits. Cortisol levels inecreased significantly in rats in groups D, E and F at subchronic and chronic levels when compared with the control. Total antioxidant capacity (TAC) increased significantly in rats in groups D and F while catalase (CAT) activities, superoxide dismutase (SOD) and reduced glutathione (GSH) levels increased significantly in rats in groups B, C, D and F respectively. Levels of malondialdehyde (MDA) increased significantly in groups B and E. The levels of BDNF in depressive states of stress-evoked Male Wistar rats therefore decreased. There was an increase in time spent in the Elevated plus maze, Novel Object recognition and Barnes maze which revealed a decline in memory, cognition and depression. In the overall, depression becomes established in the brain whenever the concentration of Cortisol suggesting the ameliorative interference of its secretion. Being a stress hormone, its influence on dwindling levels of antioxidant markers seemed corrective and advantageous to the animal under stress in the study.

Keywords: Cortisol, depression, stress, anxiety, Antioxidant capacity.