Basic study on depressive disorder in diabetes

一些流行病学和临床研究表明，糖尿病患者的精神疾病患病率高于一般人群。在本研究中，我们研究了链脲佐菌素诱导的糖尿病大鼠的行为变化，并探讨了身体和心理应激对海马BDNF水平和5-羟色胺2A（5-HT 2A）受体介导的湿狗摇反应的影响。链脲佐菌素（60 mg/kg，i. p.）诱导的糖尿病对强迫游泳实验中的不动时间和旷场实验中的自发活动没有显著影响。此外，非糖尿病大鼠和糖尿病大鼠对DOI（5-HT 2A受体激动剂）诱导的湿狗摇动反应也没有显著差异。5天暴露于物理（电击足）和心理（非电击足）应激对糖尿病或非糖尿病大鼠海马BDNF水平没有显着影响。这两种类型的应激对DOI诱导的非糖尿病大鼠湿狗抖动反应没有显著影响。在糖尿病大鼠中，反复暴露于物理应激显着增加DOI诱导的湿狗摇反应，但反复暴露于心理应激没有影响。这些结果表明，暴露于物理应激增加了链脲佐菌素诱导的糖尿病大鼠对5-HT 2A受体刺激的湿狗摇反应的易感性。

Several epidemiological and clinical studies have indicated that the prevalence of psychiatric disorders is higher in diabetic patients than in the general population. In the present studies, we examined the behavioral changes in streptozotocin-induced diabetic rats, and investigated the effects of physical and psychological stress on the hippocampal BDNF levels and on the serotonin 2A (5-HT2A) receptor-mediated wet-dog shake responses. The streptozotocin (60 mg/kg, i.p.)-induced diabetes had no significant effects on the immobility time in the forced swim test or on locomotor activity in the open-field test Moreover, there was no significant difference in the wet-dog shake responses induced by DOI, a 5-HT2A receptor agonist, between nondiabetic and diabetic rats. Five-day exposure to physical (electric footshock) and psychological (non-footshock) stress had no significant effect on the hippocampal BDNF level in diabetic or nondiabetic rats. The two types of stress had no significant effect on the DOI-induced wet-dog shake responses in nondiabetic rats. In diabetic rats, the repeated exposure to physical stress markedly increased the DOI-induced wet-dog shake responses, but the repeated exposure to psychological stress had no effect These results suggest that exposure to physical stress augmented the susceptibility to the wet-dog shake responses to 5-HT2A receptor stimulation in streptozotocin-induced diabetic rats.