Aim To investigate whether chronically un-predictable stress (CUS)-induced depression-like be-haviors of rats is associated with the variant expression of tryptophan hydroxylase (TPH)and tyrosine hydrox-ylase (TH).Methods 30 male SD rats were ran-domly divided into depression model group(MG)and control group (CG),the former was established using CUS plus solitary condition for 28 d,whereas the latter was fed normally as five rats per cage without CUS. The open field test(OFT)and the sucrose preference test were used to evaluate depressive behaviors.Both mRNA and protein expressions of TPH and TH in hip-pocampus and forebrain cortex were determined by re-al-time fluorescent quantitative PCR and western blot (WB),respectively.Results MG rats showed obvi-ous depressive behaviors with much lower locomotive activity and sucrose preference than CG.Meanwhile, the mRNA and protein expressions of TPH and TH also significantly decreased in MG rats,compared with CG rats.Conclusion The depression behaviors of rats in-duced by CUS may be associated with down-regulation of TPH and TH expression.

Aim To investigate if anti-depressive effect of venlafaxine was associated with improving oxi-dative stress and expression of hippocampus NET and 5-HTT in rat model induced by CUS. MethodsEighty SD male rats were randomly divided into four groups:model group(MG),normal group(NG), ven-lafaxine-treated normal group ( VNG ) , and venlafax-ine-treated model group ( VMG) . VNG and VMG were given venlafaxine (23. 4 mg·kg-1 ·d-1 ) once daily;NG and MG were given the same volume solvent. Soli-tary condition with chronic unpredicted stress ( CUS ) was taken to establish rat depression model. The force swimming test was used to evaluate the behavior chan-ges of experimental rats. The malondialdehyde ( MDA) level and activity of superoxide dismutase ( SOD ) in serum were determined by biochemical methods. The mRNA and protein expressions of NET and 5-HTT in
hippocampus were determined by Real-Time Reverse transcription polymerase chain reaction ( real-time RT-PCR) and Western blot ( WB) , respectively. Results Compared with NG rats, obviously increasing immo-bile time of rats in force swimming test and serum MDA level, as well as significantly decreasing SOD activity in serum was observed with clearly decreasing 5-HTT expression and elevating NET expression in hippocam-pus of MG rats. The treatment of venlafaxine distinctly suppressed changes above from CUS-induced rats. However, significant changes failed to be found in VNG rats. Conclusion The anti-depressive effect of venlafaxine may at least partly involve in improving ox-idative stress/anti-oxidative stress balance and revers-ing abnormal expression of NET and 5-HTT.

This study aimed at investigating the correlations between antidepressive effect of valproate and improvements of NET and 5-HTT expression in depressive rats leaded by chronic mild unpredicted stress(CUMS)with solitary condition. Sixty male SD rats were divided into normal group(NG), model group(MG), valproate treated-normal group(VNG), and valproate treated-model group(VMG), randomly. The changes of depressive behaviors were evaluated by the open-field test and force swimming test. The contents of MDA, activities of SOD and CAT in serum, the mRNA and protein expression of NET, 5-HTT in hippocampus were determined by biochemical methods, Real-time PCR and Western Blot, respectively. Results showed that CUMS can significantly decrease the activities in open-field test, SOD and CAT activities in serum, expression of 5-HTT in hippocampus, and obviously increase the immobility time in force swimming test, the level of MDA and expression of NET. The treatment of valproate obviously improved the changes induced by CUMS. However, the treatment of valproate had no significant influences on behaviors of NG rats. So, it revealed that improvements of the mRNA and protein expression of NET, 5-HTT may be involved in the antidepressive effect of valproate.