Comment · Wed, September 4, 2013 · Ceretropic
Piracetam induces plasma membrane depolarization in rat brain synaptosomes.
What they were answering
egadiz · 2 points
what are the symptoms of nmda downregulation/tolerance? what leads you to believe racetams may have caused nmda downregulation?
u/MisterYouAreSoDumb · Ceretropic
The NMDA receptors control tolerance to the euphoria you get from most drugs. This includes opiates, amphetamine, MDMA, etc. I have noticed since starting glutaminergic nootropics, my excitement levels have fallen, and euphoria that I get from certain drugs has diminished. I am a more level-headed and logical person, and have fewer instances of excitement and euphoria than I used to. I am in no way sad or depressed, but the change is very noticeable.
The mechanisms behind excitement and euphoria are very much linked to the NMDA receptors, and increased calcium transmission through the ion channels. It might be causing NMDA down-regulation, or it could be a downstream mechanism within the neuron itself. Racetams have been proven to increase the membrane potential of neurons, which allows more calcium to pass through the ion channels. It's no surprise that the body would try and compensate for this enhancement, as it does with every other mechanism that brings it out of homeostasis. My postulations are arising from my anecdotal experience. However, there are multiple studies out there that fit into this theory.