Expressions of GABARB2 in brain regions of rats with high-level and low-level aggressive behavior

Abstract

Objective To compare the mRNA and protein expression levels of γ-aminobutyric acid receptor B2 (GABABR2) in brain regions of male rats with high level aggressive behaviors and low level aggressive behaviors respectively, and provide clues for exploring mechanism of GABA in aggressive behaviors. Methods Wistar male rats were randomly divided into two groups: the normal group and the aggressive behavior group. Then social isolation and resident intruder stresses were used to establish high level and low level aggressive behavior in the aggressive behavior group. The mRNA and protein level of GABABR2 in parietal cortex, prefrontal cortex, hypothalamus and hippocampus of the three groups rats (n=10 in each group) were detected using RT-PCR and Western blot respectively. Results The GABABRB2 RT-PCR/Western blot relative integrated optical density of parietal cortex, prefrontal cortex, hypothalamus and hippocampus in the normal group rats respectively were. Those of the above four brain regions in high aggressive behavior group rats respectively were(0.507±0.049/0.626±0.038), (0.609±0.049/0.652±0.010), (0.359±0.030/0.731±0.044)and(0.296±0.054/0.452±0.079) were significantly lower (P<0.05) compared with the normal group rats. In the low aggressive behavior group rats, the GABABRB2 RT-PCR/Western blot relative integrated optical density of parietal cortex and hippocampus increased statistically(P<0.05), while those of prefrontal cortex and hypothalamus decreased obviously (P<0.05). all in comparison with the normal group rats. Conclusion Different expression levels of GABABR2 in parietal cortex, prefrontal cortex, hypothalamus and hippocampus are relative to aggressive behaviors, which might be one of the mechanism for GABA in aggressive behaviors. Key words: Aggressive behavior; Rat; γ-aminobutyric acid receptor B2; Brain region