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 .
ABSTRACT
Objective To investigate the effects of S 100B, AQP4, and CX43 on the function of the blood brain barrier in the hippocampus of diabetic rats with depression .Methods Rats were divided into the diabetic group [ two weeks of high-fat diet and injection of Streptozotocin (STZ, 38 mg/kg)], depression group(chronic unpredictable stress for 28 days) , the diabetes mellitus with depression group ( combined with the above two methods ) , and the control group .The behavior of rats was evaluated with open-field test and Morris test .The expressions of AQP 4 and CX43 in rat hippocampus blood-brain barrier were detected by immunocytochemistry .Serum S100B level was detected by ELISA.Results Compared with control group, the number of autonomic activity and the space exploration times were decreased, the escape latencies were significantly longer in the Morris water maze test(P<0.05 or P<0.01) of the diabetes group and depression group; Serum S100B levels increased significantly ( P<0.01);the expressions of AQP4 and CX43 were decreased(P<0.01).Compared with diabetic group, the number of auto-nomic activity and the space exploration times were decreased , the escape latencies were significantly longer in the Morris water maze test( P<0.05 or P<0.01) of the diabetes group and depression group;Serum S 100B lev-els increased significantly( P<0.05);the expressions of AQP4 and CX43 were decreased(P<0.05 or P<0.01). Conclusions S100B, AQP4 and CX43 expression disorder may be one of the mechanisms of diabetes mellitus complicated with depression.