This study was aimed to study the possible adverse effect of NDT treatments on female rats by behavioral, biochemical and electrophysiological approaches.

Dexamethasone (DEX) is a synthetic glucocorticoid and frequently used as anti-inflammation agent. It is also extensively used as an early treatment for preventing the onset of chronic lung disease in premature born infants. Neonatal DEX treatment (NDT) had been proven to have long-term adverse effect in central nervous system. Our previous study showed that the NDT male rats elicited significant increase in depression-like behaviour.  the formation of LTP in the hippocampus and the amygdala will be affected by the neonatal DEX treatment remains to be further studied.

New-born Wistar female pups received tapering dosage of NDT from postnatal day one to day three (0.5, 0.3, & 0.1 mg/kg, intracutaneously). They were then subjected to behavioural, biochemical, and electrophysiological experiment at the age of 6 weels old (juvenile) and 10 weeks old (adulthood).

Results showed the percent time of immobilization in forced swimming test (FST) was increased in NDT group which suggested an elevation of depression-like behavior in NDT female rats. In addition, real-time PCR results demonstrated a significant decrease of the expression of GPR30 in both hippocampus and amygdala of the adult NDT female rats compared with the corresponding control groups. In addition, the high-frequency stimulation induce hippocampal long-term potentiation was decreased in NDT female and can be restored with G1 co-treatment. 

In summary, our results demonstrated that NDT had long-term adverse impact on the hippocampal and amygdaloid function of the female ratswhich might responsible to the increase of depression-like behavior in NDT female rats. Further experiments such as intra-cranial injection of G1 into the hippocampus or amygdala, is ongoing for determining the role of GPR30 on the NDT induce depression-like behavior in female rats.