The effect of neuroleptics in single administration on the expression of genes of the jun family was studied in the rat striatum. jun B, but not jun D was dose-dependently and transiently induced. This effect was blocked by pretreatment with a specific dopamine D2 agonist. The expression of c-jun was also stimulated, although this did not reach statistical significance. Thus dopamine D2 receptors differentially regulate the expression of jun family members in the striatum.