The effects of fluoxetine on oligodendrocytes in the hippocampus of chronic unpredictable stress-induced depressed model rats.

Depression is a mental illness which is harmful seriously to the society. This study investigated the effects of fluoxetine on the CNPase oligodendrocytes in hippocampus of the depressed rats to explore the new target structure of antidepressants. Male Sprague-Dawley rats were used to build chronic unpredictable stress (CUS) depressed model of rats. Then, the depressed rats were divided into the CUS standard group and the CUS + fluoxetine (CUS/FLX) group. The CUS/FLX group was treated with fluoxetine at dose of 5 mg/(kg·d) from the fifth week to seventh week. After 7 weeks CUS intervention, the sucrose preference of the CUS standard group was significantly lower than that of the control group and the CUS/FLX group. The stereological results showed that the total number of the CNPase cells in the CA1, CA3, and DG subfield of the hippocampus in the CUS standard group were significantly decreased, when compared with the CNPase cells in the control group. However, the total number of the CNPase cells in the CA1 and CA3 subfield of the hippocampus in the CUS standard group was significantly decreased when it compared with CNPase cells in the CUS/FLX group. Therefore, fluoxetine might prevent the loss of CNPase oligodendrocytes in CA1 and CA3 subfields of hippocampus of the depressed rats. The oligodendrocytes in hippocampus may play an important role in the pathogenesis of depression. The current result might provide structural basis for the future studies that search for new antidepressant strategies.