The significance of complete distributional analysis of the serotonin receptor

Abstract

Monoamines, including serotonin, dopamine, noradrenaline, and adrenaline are essential neurotransmitters of the central nervous system (CNS). Although monoamine-containing neuronal somata are located in the brainstem, their axons project throught the brain. Thus, the monoamine system features a widespread network and is involved in diverse brain functions. Because individual neural functions are dependent on different types of monoamine receptors, it is important to understand the expression of each receptor within the CNS. In order to further elucidate the monoamine system, we performed distributional analysis in the entire CNS, targeted for 5-hydroxytryptamine 3A receptor (5-HT3AR), the only ionotropic receptor amongst the monoamine receptors. Because our method has high sensitivity and contrast, our findings reveal 5-HT3AR expression in novel regions as well as detailed localization throughout the entire CNS. These findings will facilitate further studies on the serotonin system. In this article, we illustrate the detailed distributional analysis of 5-HT3AR expression and suggest a renewed focus on the importance of whole distributional analysis of monoamine neurotransmitters. We hope for future studies to further investigate distribution of monoamine receptors throughout the entire CNS.