Acıbadem Üniversitesi Sağlık Bilimleri Dergisi 2019 , Vol 10, Issue 3
An Evaluation of The Effects of Two Chronic Immobilization Stress Protocols On Depression/anxiety- Related Behavior In Male Rats
Zafer Şahin1,Alpaslan Özkürkçüler2,Aynur Koç3,Hatice Solak2,Raviye Özen Koca2,Pınar Çakan4,Zülfikare Işık Solak Görmüş2,Selim Kutlu2
1Karadeniz Technical University Faculty of Medicine, Department of Physiology, Trabzon, Turkey
2Necmettin Erbakan University Meram Medical Faculty, Department of Physiology, Konya, Turkey
3Hitit University Faculty of Medicine, Department of Physiology, Çorum, Turkey
4Inonu University Faculty of Medicine, Department of Physiology, Malatya, Turkey
DOI : 10.31067/0.2019.186 Objective: The effect of acute and chronic stress models on depression and/or anxiety-like behavior in rodents has been widely studied, but with contradictory results. This may be due to differences in the sex and age of the animals studied or inherent differences in the stress models used. Therefore, this study aimed to evaluate the effects of two immobilization stress protocols on depression/anxiety-like behaviors in adult male rats.

Materials and Methods: Adult Wistar rats were randomly divided into three groups (n=10) comprising: control, immobilization stress-1 (45 minutes daily for a period of ten days), and immobilization stress-2 (45 minutes twice a day for a period of ten days). Stress-related behavior was evaluated by means of the open field and forced swim tests. In addition, change in body weight, fasting blood glucose, and serum corticosterone were measured.

Results: In the open field test, the percentage of time spent in the central area and mean velocity were significantly lower in the immobilization stress-1 and immobilization stress-2 groups as compared to the control group (p < 0.05 and p < 0.01, respectively). Movement ratios were lower in both immobilization stress groups than in the control group (p < 0.001 and p < 0.01, respectively). In the forced swim test, the duration of swimming, climbing and immobility behavior in both immobilization stress protocols did not differ from the control group. Serum corticosterone levels were higher in the immobilization stress-1 and immobilization stress-2 groups than in the control group (p <0.05), but no overt differences were determined in the percentage change in body weight or the fasting blood glucose level between the stress protocol groups and the control group (p > 0.05).

Conclusion: We may conclude that immobilization stress-1 and immobilization stress-2 protocols do not cause depression-like behavior in adult male rats. However, anxiety-like behaviors predominated in both stress protocol groups. Keywords : immobilization stress, depression, anxiety, open field, forced swimming test