1. The Division of Biological Research on Drug Dependence, Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden.
2. Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia.
3. Institute of Biochemistry, Siberian Division of the Russian Academy of Medical Sciences, Novosibirsk, Russia.
4. Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia.
5. Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, Virginia.
6. Spinal Cord and Brain Injury Research Center and Sanders-Brown Center on Aging, University of Kentucky, Lexington, Kentucky.