Originally Posted by Mr.Tree

when a pill is taken, mdma is absorbed by the brain via serotonin transporters. the serotonin transporters become confused and begin to transport serotonin out of the cell, and not into the cell. and thus this causes the serotonin to be trapped in the synaptic cleft, where it binds again and again with serotonin receptors, stimulating an ecstasy high.