Changes of content of monoamine neurotransmitters and expression of neurotrophic factors in brain regions of rat models of anxious depression / 中国实验动物学报

ABSTRACT

Objective To study the content of monoamine neurotransmitters and neurotrophic factor in the hippocampus, amygdala and prefrontal cortex in anxious depression rats, and explore the possible pathogenesis.Methods 60 SD rats were randomly divided into normal group, vehicle group, anxiety group, depression group, and anxious depression group, 12 rats in each group.Chronic restraint stress combined with corticosterone injection was used to establish anxiety and depression model, the modeling time was 21 d.After modeling, elevated plus maze test, open field test, and forced swimming test were used to evaluate the anxiety and depression-like behavior, HPLC-ECD was used to detect the content of 5-HT, NE, and DA in the hippocampus, amygdala, and prefrontal cortex of rats.Western-blotting was used to detect the expression of BDNF and NT-3 in rats.Results Rats in anxious depression model group were comparable to the anxiety group in time and frequency entering open arm time, and number of locomotor activity in open field, and it had a significant difference when compared with the control and depression groups (P<0.01 or P<0.05).Immobile time in anxious depression model rats was increased significantly when compared with the control and anxiety groups (P<0.01).Meanwhile, compared with the control group, 5-HT in hippocampus and 5-HT, NE in amygdala or prefrontal cortex were significantly decreased in the depressive rats with anxiety (P<0.01 or P<0.05).Moreover, the content of BDNF and NT-3 was significantly decreased in each brain regions compared with the control group (P<0.01 or P<0.05), and BDNF levels were obviously decreased compared with the anxiety group (P<0.05).Conclusions Rats of anxious depression have significant anxiety and depression-like behaviors.Its mechanism may be associated with the down-regulation of monoamine neurotransmitters and neurotrophic factors BDNF and NT-3 in hippocampus, amygdala, and prefrontal cortex region.