Posted by oracle on January 24, 2003, at 10:30:34
In reply to Ecstasy, posted by Caleb462 on January 23, 2003, at 23:03:27
http://www.maps.org/media/peoplesprozac.html
Not necessarily true, says O'Callaghan, who works for the federal Centers for Disease Control and Prevention. He says these ads are misleading because they leap beyond what we already know -- that administering the popular club drug, also known as MDMA, carries the aftereffect of temporarily decreasing serotonin. "It looks like a blank slate, but it comes back," says O'Callaghan. "I'm not saying that MDMA isn't bad. I'm just saying that there's no evidence that it destroys serotonin neurons."
O'Callaghan thinks this view is too simplistic. He says that just because the drug affects serotonin doesn't mean the damage takes place in those neurons. The rewiring, he argues, stems from something other than injury. "The [pruning phenomenon] is not necessarily reflective of damage," he says, "just profound and long-lasting changes."
He contends that if MDMA caused nerve-cell degeneration, star-shaped cells would form, leading to an increase of the glial fibrillary acidic protein, or GFAP. "Any chemical known to damage the brain has caused an increase in GFAP," explains O'Callaghan. "We don't see that response with MDMA." While detractors agree that GFAP is a valid indicator of brain damage, they still take issue with O'Callaghan's measurements. "MDMA is a potent brain neurotoxin. The entire field reads the literature as such," says Ricaurte. "Are all 100 nails in to shut the coffin? No. But are there 70, 85, 90? At what point do you look at the data and say it's met a certain criteria? That criteria's been met long ago."O'Callaghan doesn't get invited to speak at many conferences anymore -- even though he has been publishing extensively in this area for years. So politicians end up listening less to dissidents like him than to mainstreamers like Ricaurte and Dr. Alan Leshner, director of the National Institute on Drug Abuse. In a hearing before the Senate Subcommittee on Governmental Affairs this past July, Leshner stated, "There is substantial evidence to show that MDMA damages brain cells. Within the scientific community we cannot say with absolute certainty how and to what extent... but there is across-the-board agreement that brain damage does occur."
But O'Callaghan believes the whole idea of neurotoxicity -- of brain damage -- has been tossed around too freely. A single dose of reserpine, a prescription drug used to treat hypertension, markedly lowers serotonin levels for extended periods. "It's just as neurotoxic as MDMA, if you equate neurotoxicity with serotonin decrease," he says. "But if you look at damage as defined by loss of structure, you don't see it [with MDMA], even in whopping doses."
The long-term consequences of MDMA use are similarly ill-defined. "The evidence up to date has been pretty crummy," Dr. H. Valerie Curran, a psychopharmacology professor at University College London, told the NIDA conference in July, noting that the most consistent findings relate to learning and memory. "The effects are subtle, but have real implications." If MDMA does indeed cause brain damage by pruning the neuronal pathways, then a whole host of serotonin agents, including Prozac and Adderall, could be rewiring, and thus damaging, our brains. The latter -- often given to hyperactive children -- is particularly worrisome, say critics, because it also affects dopamine, which helps the immature brain develop normally. A paper co-authored by O'Callaghan in Brain Research last year concluded that all compounds acting on the brain's serotonin system can cause changes in serotonin neurons. O'Callaghan says the creation of these abnormalities, including corkscrew-shaped neurons, could be part of Prozac's desired therapeutic effect.
poster:oracle
thread:137145
URL: http://www.dr-bob.org/babble/20030119/msgs/137315.html