Corrigall WA, Coen KM, Adamson KL, Chow BL. The mu opioid agonist DAMGO alters the intravenous self-administration of cocaine in rats: mechanisms in the ventral tegmental area. Psychopharmacology 1999; 141 : 428-35
 Robinson TE and Kolb B. Alterations in the morphology of dendrites and spines in the nucleus accumbens and prefrontal cortex following repeated treatment with amphetamine and cocaine. Eur. J. Neurosci. 1999; 11: 1596-1604.
 Whiseler, K., Kelz, M. B., Chen, J.S., Nestler, E.J. and Self, D.W. Effects of conditional overexpression ofΔFosB in nucleus accumbens on cocaine self-administration and relapse to cocaine-seeking behavior. Soc. Neurosci. Abstr. 1999; 25:811.
 Peakman MC, Colby C, Perrotti LI, Tekumalla P, Carle T, Ulery P, Chao J, Duman C, et al. Inducible brain-region specific expression of c-jun in transgenic mice decreases sensitivity to cocaine. Brain Res. 2003 Apr 25; 970(1-2): 73-86.
 Yuferov V, Zhou Y, Spangler R, et al. Acute “ binge” cocaine increases muopioid receptor mRNA levels in areas of the rat mesolimbic mesocotrical dopamine system. Brain Res. Bull. 1999; 48: 109-112.
 Trujillo KA and Akil H. Excitatory amino acids and drugs of abuse: a role for N-methyl-D-aspartate receptors in drug tolerance, sensitization and physical dependence. Drug Alcohol Depend. 1995; 38: 139.