Study on model of tree shrew induced by chronic corticosterone injection in anxious depression / 中国药理学通报

ABSTRACT

Aim To investigate the effects of chronic corticos-terone injection on anxiety and depression-like behavior of tree shrews, evaluate the predictability of drug and establish a novel animal model of anxious depression .Methods Twelve Chinese and Burma tree shrews were randomly divided into normal group, model group and venlafaxine group .The anxious depres-sion model of tree shrew was established by chronic corticoster-one injection ( ih, 27 mg· kg-1 , 21 d) .The venlafaxine group received intragastric administration (6 mg· kg-1).Autonomous activity score, sugar water preference test and Morris water maze test were used to evaluate the anxiety and depression-like behav-ior of tree shrews .The expressions of CRH , ACTH and COR in the tree shrew plasma were determined by Elisa kit .The con-tents of monoamine neurotransmitters of tree shrews in the hippo-campus , amygdala and prefrontal cortex were detected by HPLC-ECD.Results Compared with the normal group , the autono-mous activity score , sugar water partial eclipse degree and the learning and memory ability significantly decreased (P<0.01), while the contents of CRH , ACTH and COR significantly in-creased ( P<0.05) , and the contents of 5-HT, NE and DA in the hippocampus , amygdala and prefrontal cortex declined in the model group(P<0.05).In the venlafaxine group, the learning and memory abilities of the tree shrews were improved , the lev-els of CRH and COR in plasma were significantly decreased ( P<0.05), and the contents of 5-HT, NE and DA were increased (P<0.05).Conclusions The tree shrews of anxious depres-sion have obvious HPA axis hyperactivity and monoamine neuro-transmitter disorder , and venlafaxine can reverse this phenome-non, indicating that the tree shrews model of anxious depression has drug predictability , which is a kind of novel animal model of anxious depression closer to human in clinic .