Mice lacking melatonin MT2 receptors exhibit attentional deficits, anxiety and enhanced social interaction.
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
melatonin | neutral | cognitive processes | - | - | affects | #1 |
melatonin | neutral | the brain circuitry underlying psychiatric diseases | - | - | modulates | #2 |
melatonin MT1 receptors | neutral | the circadian effects of the hormone | - | - | mediate | #3 |
MT2 receptor | neutral | cognition | Mice with a genetic deletion of the MT2 receptor | - | plays a role in | #4 |
MT2 receptor | neutral | anxiety | Mice with a genetic deletion of the MT2 receptor | - | modulates | #5 |
MT2 receptor | neutral | social interactions | Mice with a genetic deletion of the MT2 receptor | - | modulates | #6 |
BACKGROUND: Aside from regulating circadian rhythms, melatonin also affects cognitive processes, such as alertness, and modulates the brain circuitry underlying psychiatric diseases, such as depression, schizophrenia and bipolar disorder, via mechanisms that are not fully clear. In particular, while melatonin MT1 receptors are thought primarily to mediate the circadian effects of the hormone, the contribution of the MT2 receptor to melatonin actions remains enigmatic. AIMS: To characterise the contribution of MT2 receptors to melatonin's effects on cognition and anxiety/sociability. METHODS: Mice with a genetic deletion of the MT2 receptor, encoded by the RESULTS: CONCLUSIONS: The results confirm that the MT2 receptor plays a role in cognition and also modulates anxiety and social interactions. These data provide new insights into the functions of endogenous melatonin and will inform future drug development strategies focussed on the MT2 receptor.