Fig. 3. Schematic representation depicting the effects of ethanol (40 mM), cocaine (20 mg/kg), and ethanol-cocaine treatments on Fos-like protein in striatonigral neurons. Ethanol by itself has no effect on the cellular expression of this transcription factor protein. In contrast, cocaine treatment markedly induces the expression of Fos-like protein, particularly in the dorsal caudate putamen. However, concomitant administration of ethanol and cocaine reduces the expected expression of the c-fos gene. Sterile NaCl was used as vehicle.