نقش استرس رواني در بروز يا تشديد ديابت شيرين ، تغييرات سطح گلوكز، كورتيزول و اختلاف وزن در رات

The effect of psychical stress on cause and exacerbation of diabetes mellitus, serum glucose and cortisol levels, and body weight in rats

Background and Aim: In this study the effect of chronic psychical stress on the serum glucose level (SGL), serum cortisol level (SCL) and body weight were investigated to determine the possible causal link between psychical stress and diabetes mellitus. Methods: This experiments were investigated in 56 nondiabetic and Wistar male rats (200-250gr) divided to seven groups (n=8). Water immersion stress was used as chronic psychical stress one minute evrey hour for 4 hours everyday for a priod of 14 days. After the experiment, a blood sample was collected. The serum glucose level was measured by the glucose oxidase method, and serum cortisol level was measured by radioimmunoassay method. Difference in body weight was also calculated. Results: Our results showed that: 1) Although this chronic psychical stress caused a significant increase in SGL (about 22%), in steressed nondiabetic rats (p<0.01), did not cause diabetes mellitus (DM). It seems that this kind of stress induced a prediabetic condition in nondiabetic rats and exacerbated the disease in the diabetic rats. 2)Increase of SGL in stressed nondiabetic (about 22%) and stressed diabetic (about 16.4%) rats was approximatly similar (p<0.01). 3)SCL showed no significant increase in repeated chronic stress. 4)Increase of SCL (about 39.3%) in diabetes mellitus was significant (p<0.05). 5)This kind of stress increased SCL approximatly similar in stressed nondiabetic (about 12.7%) and stressed diabetic (about 8.9%) rats. 6)Effect of diabetes mellitus in comparison with stress on the SCL (about 23.6%) was much higher than that of the psychical stress (p<0.05), in other words DM is a strong stressor for physioligical systems of the body. 7)This psychical stress caused a significant decrease of body weight in nondiabetic (about 3 7.42%) and diabetic (about 2.94 fold) rats. 8)Effect of diabetes on weight loss was much higher than that of psychical stress (p<0.01). 9) Stress caused a much higher weight loss in diabetic rats than in nondiabetic rats (p<0.01) indicating the additive effects of stress and diabetes on changes of weight, probably stress changes hormonal secretion (such as GH) in diabetic and nondiabetic rats. Conclusion: Chronic psychical stress induced hyperglycemic and a prediabetic condition and did not cause diabetes mellitus. In the other hand, diabetes increased serum cortisol level that this effect was much higher than that of the psychical stress. In addition effect of diabetes on weight loss was much higher than that of psychical stress .In the end stress caused a much higher weight loss in diabetic rats than in nondiabetic rats.