N&PD Moderators: Skorpio | thegreenhand
On your original post in that other thread you seemed to use SERT and serotonin interchangeably sometimes - I assumed by the context that you meant serotonin in most cases and that serotonin depletion was the topic, rather than SERT hypoexpression.
SERT expression may not return to 100% normal in some cases in humans, but this could be some sort of compensation rather than a reflection of nerve terminal loss or an issue with synthesizing new SERTs. The same can be said with DAT hypoexpression after amphetamines in humans.
Changes in receptor expression are a different animal as well, as people with mental illness can often show altered receptor expression. That being said, I will say that some former MDMA abusers have upregulation of 5-HT2A in cortex, which could indicate solely decreased pre-synaptic release or maybe loss of some feed-forward excitation that normally would result in increased pre-synaptic release.
In one case, MDMA abusers actually showed about 10% increased dopamine in the putamen with IIRC normal levels elsewhere, but that could just be a typical senstization-to-amphetamine type thing (similar to the persistent locomotor sensitization that animals can show after a single dose of amphetamine).
Just to be clear, I've never argued that former MDMA abusers don't have abnormalities visible with neuroimaging (especially the heavy chronic abusers) and neurocognitive abnormalities, but my main argument was that people aren't having issues 1 year post-MDMA because of a vesicular shortage of serotonin
I'd be happy to read your upcoming post, toodles
CY