Amphetamines + MDMA?

I hope this has not been canvassed elsewhere, anyway...
I have heard from numerous sources that when you combine speed or meth with ecstacy the chances of causing neurotoxicity increases.
I am interested in knowing if this is indeed true, and if so, how?
Does combining MDMA with a dopamine agonist like speed increase the chances of serotonin neurons reuptaking dopamine later?
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The woods are dark and deep, and you have miles to go before you sleep...

There is a fairly extensive thread on this... uh... somewhere. Hah, good luck finding it buddy I have a feeling if you do look it could prove to be good, but inconclusive... um, or maybe I just don't remember.
Sorry, this wasn't any help at all, eh.

hmm.. this is odd. this is exactly what i have been looking up today. hmm.. maybe a coincidence but maybe not. have you done the esafe quiz? the last question is on this in particular.
According to the info i have read but am unable to source right now.. yes - combining speed and MDMA will increase neurotoxicity. the reason being as you stated.
Dopamine has been found to be an important part of neurotoxicity caused by MDMA - shown in detail in the dance safe slideshow. This is the only tid bit i could find at the moment.. but there is info on this somewhere. damn i wish bluelight had its search function back.. :'(
"Pre- treatment of an animal with a drug which blocks dopamine release will also block MDMA neurotoxicity. Also, serotonin specific releasing agents which are non-dopaminergic have been synthesized and been found to be devoid of MDMA's neurotoxicity in animals, they have also been found to be devoid of MDMA's psychological effects" - erowid MDMA vault #7.
It follows that an increase in dopamine release would result in an increase in neurotoxicity. hence my conclusion also - mdma and speed = more neurotoxicity.
hmm.. anyone else got some info?