SLC6A4 and psychiatric disorder: The large body of evidence implicating Slc6a4 in behavioral traits and psychiatric disorders [42, 43], along with the strong association of Platelet homeostasis, suggest that serotonin and its signaling play key roles in prepulse inhibition: in addition to modulating brain functions, serotonin is abundantly stored in platelets outside the brain and regulates vasoconstriction, dilation, and other cardiac functions [45].