Neurogenesis in the dentate gyrus of adult rat following conditioned fear stimuli / 中华行为医学与脑科学杂志

ABSTRACT

Objective To investigate neurogenesis in the dentate gyrus of adult rat following conditioned fear stimulus.Methods 24 adult male rats were randomly divided into conditioned fear stimulus group and control group,and all rats were intraperitoneally injected bromodeoxyuridine(BrdU)3 days before conditioned fear stimuli.Animals in conditioned fear stimulus group were given monotone matching foot shock and made conditioned fear stimulus model,animals in control group only give monotone.Freezing time was detected before stimuli and 7th,14th days after stimuli,then rats were sacrificed 7th or 14th day after fear conditioned stimulus,and immunohistochemistry for Brdu was detected.Results Behavioral assessment showed that the percents of freezing time in conditioned fear stimulus group 7th,14th days after conditioned fear stimulus were significantly high(88.68%,91.33%)than those in control group(11.18%,14.23%,P<0.01)and before stimulus(24.11%,16.11%,P<0.01).Compared to control group(1567±28,580±5),Brdu positive cells in dentate gyrus of rat in conditioned fear stimulus group(1364±21,296±22)were decreased,and it reached to a statistical significance on 14th day (P<0.05).Conclusion The decreased neurogenesis in the dentate gyrus of adult rat following conditioned fear stimuli may have relation to fear and other emotion memory.