Effects Of Inhibition Of PV Interneurons In Anterior Cingulate Cortex On Behaviors Related To Mental Disorders In Mice

Objective: The function of anterior cingulate cortex(ACC)involves many fields such as emotion and cognition and so on.Many studies suggest that there are structural and functional abnormalities of ACC in patients with mental disorders,and the abnormalities of GABA inhibitory interneurons in their brains,especially the dysfunction of parvalbumin(PV)interneurons.In this study,DREADD was used to study the function of PV interneurons of ACC in the behavior related to mental disorders in mice.Methods: The technique of designer receptors exclusively activated by designer drugs(DREADD)was used to specifically target the PV interneurons in PV-Cre mice.CNO was injected intraperitoneally to inhibit PV interneurons in mouse ACC,and behavioral tests including open field test,marble burying,elevated cross maze,light /dark box,three chamber social interaction,novel object recognition,Y maze test,fear conditioning,pre-pulse inhibition were carried out to reveal the behavioral phenotypes of experimental mice.Results: CNO successfully reduced the spontaneous electrical activity of PV interneurons in ACC.Compared to the control group,mice in the experimental group exhibited trends of increased spontaneous movement in the open field test(p=0.23)and decreased social interaction index during the three chamber free exploring test(p=0.20).They also displayed trends of reduced entry into the open arm during the elevated cross maze(p=0.12)and increased stay in the illuminated chamber in the light/dark box test(p=0.13).However,no statistical significance was achieved.Meanwhile,there were no overt difference between the two groups in the tests of marble burying,novel object recognition,Y-maze,fear conditioning and PPI.Conclusion: The current results did not provide supporting evidence for the involvement of PV interneurons in schizophrenia-like behavioral manifestation.Further experiments in larger scale or using alternative techniques shall be warranted in future.