FIGURE 3.

Colocalization of the D1 and D2 receptor with dynorphin and enkephalin in rat caudate putamen. A and B, confocal images showed that the D1R and D2R were colocalized with DYN or with ENK in CP (white arrows). C and D, neurons coexpressing DYN and ENK also expressed D1R or D2R (white arrows). DYN and ENK also exhibited coexpression in the absence of D1R (yellow arrows). E and F, neurons that expressed only D1R were positive for DYN, and neurons expressing only D2R were positive for ENK (yellow arrows).