ATLANTA -- Researchers at the Yerkes National Primate Research Center of Emory University are the first to demonstrate a combination of drug therapies targeting the region of the brain that controls drug abuse and addiction significantly reduces cocaine use in nonhuman primates. These findings, which appear in the June issue of the Journal of Pharmacology and Experimental Therapeutics, have implications for developing treatments for cocaine addiction in humans.
Led by Leonard Howell, PhD, an associate professor in Yerkes' Neuroscience Division, the Yerkes researchers observed the innovative combination of dopamine transporter (DAT) inhibition and serotonin transporter (SERT) inhibition was effective in limiting cocaine use in rhesus macaques who are trained to self-administer cocaine. "It appears DAT inhibition serves to substitute for cocaine, while SERT inhibition may limit the abuse potential of the medication," said Howell. "Our results, therefore, showing a combination of DAT and SERT inhibition were more effective than either alone are very promising."
This first-time finding was the promising end result of a several-step process. Howell and his colleagues began by administering a pretreatment of DAT inhibitors to confirm their effectiveness in reducing drug use. DAT inhibitors have long been used in addiction studies because they elicit reinforcing properties in the brain similar to those experienced as a result of taking cocaine.
The research team then substituted the DAT inhibitors for cocaine in order to determine their effectiveness in maintaining the use of the medications. Finally, Howell and the team administered a pretreatment with combined DAT inhibition and SERT inhibition, which is known to block the chemical effects of cocaine in the brain and reduce addictive properties, to determine if cocaine use was further reduced. "Pretreatments with the combination therapy were very effective in eliminating cocaine use. Moreover, drug substitution tests with the medication indicated it should have limited abuse potential in humans," added Howell.
Compliance is going to be a problem with any use of drugs which must be used continually to treat abuse of other drugs. Gene therapies against substance cravings or other therapies that cause lasting changes in the brain would be far more reliable. However, the discovery of effective drug therapies would point the way toward what gene or cell therapies would need to alter in order to be effective.
As I've argued in my previous post the potential savings from successful drug treatments run into the hundreds of billions per year.
|Share |||Randall Parker, 2004 May 27 02:03 PM Brain Addiction|