Serotonin receptor 4 in the hippocampus modulates mood and anxiety.

Serotonin receptor 4 (5-HTR) plays an important role in regulating mood, anxiety, and cognition, and drugs that activate this receptor have fast-acting antidepressant (AD)-like effects in preclinical models. However, 5-HTR is widely expressed throughout the central nervous system (CNS) and periphery, making it difficult to pinpoint the cell types and circuits underlying its effects. Therefore, we generated a Cre-dependent 5-HTR knockout mouse line to dissect the function of 5-HTR in specific brain regions and cell types.