Expression of 11β-hydroxysteroid dehydrogenase type 1 on hippocampus of rat with chronic unpredictable mild stress / 中华行为医学与脑科学杂志

ABSTRACT

ObjectiveTo investigate the roles of 11 β-hydroxysteroid dehydrogenase type 1 ( 11 β-HSD1 )on hippocampus of rat with chronic unpredictable mild stress (CUMS).MethodsTwenty-four male SpragueDawley rats were randomly divided into control group and depressive model group. Chronic unpredictable mild stress (CUMS) was used to make up depressive animal model.Behavioral changes were recorded by body weight measuring,sucrose consumption test (SCT) and open field test (OFT),respectively.The mRNA transcription of 11β-HSD1 in hippocampus tissues of the rats were detected by real-time RT-PCR,and the protein expression of 11β-HSD1 were detected by western blot and immunofluorescence.ResultsBcforc starting CUMS protocol,the rats exhibited equivalent weight and sucrose consumption.Twenty-eight days after CUMS protocol,behavior parameters such as body weight,sucrose consumption,nunber of crossing,and number of rearing were significantly decreased in rats exposed to CUMS group compared with control group (P ＜ 0.05,P ＜ 0.01 ).Correspondingly,realtime RT-PCR assays showed the mRNA expression of 11 β-HSD1 in the hippocampus of CUMS group,which was (31 ±9) ％ lower than that of control group.Meanwhile,the protein expression of it in CUMS group was lower than that of control group (P ＜ 0.05 ).Inmunofluorescence revealed that the number of positive 11 3-HSD1 cells was high (223 ± 13) in the control group,while the number was decreased prominently (92 ± 11 ) in the CUMS group (P ＜ 0.01 ).ConclusionDepressive behavior of rats is induced and the expression of 11 β-HSD1 in the hippocampus is decreased prominently by CUMS,the mechanism of which is at least related to the low expression of 11β-HSD1 and disturbance of glucocorticoid metabolism caused by CUMS.