Alterations of Group I mGluRs and BDNF Associated with Behavioral Abnormity in Prenatally Stressed Offspring Rats

Substantial evidence reveals that prenatal stress is closely linked with abnormal behavior in offspring, but the mechanism remains unclear. In this study, our aim was to observe the alterations of behaviors, metabotropic glutamate receptor-1/5 (mGluR1/5) and brain-derived neurotrophic factor (BDNF) in various brain regions of prenatally stressed offspring rats. The forced swimming test (FST) and the open field test (OFT) were carried on 1-month-old offspring rats. The expression levels of mGluR1, mGluR5, and BDNF mRNA were measured in various brain regions of the offspring rats. Our results showed that the immobile time in the FST was significantly increased in the late prenatal stress (LPS) group compared with that in the control group, especially in the female rats. Similarly, in the OFT, the rats in both the mid prenatal stress (MPS) and LPS groups demonstrated anxiety-like behavior, especially the male rats in the LPS group. The expression of mGluR1 protein was increased in the hippocampus and prefrontal cortex of rats from the LPS group, as well as in the prefrontal cortex of rats from the MPS group. Meanwhile, the expression of mGluR5 protein was facilitated in the hippocampus and prefrontal cortex of rats in the LPS group. The expression of mGluR5 protein was increased in the striatum of the female rats in both MPS and LPS groups, and only in the male rats from the LPS group. In addition, the reduced BDNF mRNA level was detected in the hippocampus and prefrontal cortex in the LPS rats, and in the striatum of the female rats in LPS group. These results indicate that alterations of the mGluR1, mGluR5 and BDNF mRNA may contribute to the depression-like and anxiety-like behaviors of prenatally stressed offspring rats.