Fig. 4.

Increased dopamine D3 receptor expression in MAM-treated rats. Quantitative RT-PCR was performed on RNA extracted from the nucleus accumbens and VTA of saline- and MAM-treated rats. A, expression data demonstrate higher mRNA levels of D3 compared with D2 receptor expression throughout both the NAc and VTA. B, MAM-treated rats display a significant increase in the expression of the dopamine D3 receptor throughout the NAc but not VTA. It is noteworthy that there were no significant changes in the mRNA expression of any of the other examined markers. *, significant difference from saline; p < 0.05; two-way ANOVA with Holm Sidak post hoc (n = 5 rats/group).