5-HT3 and 5-HT4 receptors in terminal regions of the mesolimbic system

In this brief review, we present the evidence for the regulation of the mesolimbic dopamine system by 5-HT3 and 5-HT4 receptors. A range of studies show good evidence that 5-HT3 receptor antagonists reduce raised mesolimbic dopamine activity by blocking 5-HT3 receptors in terminal parts of the mesolimbic dopamine system. Few studies have been conducted on the effects of 5-HT4 receptors on dopamine systems. However, it is clear that 5-HT4 receptors are present in relatively high density in areas of the brain that contain dopamine and preliminary studies show that 5-HT4 receptors may regulate the release of this transmitter.