Acute ketamine decreased D1R expression in the ventrolateral caudate-putamen. Subchronic ketamine did not affect D1R and D2R expression. Increased D2R and DAT expression by subchronic ketamine was found in the midbrain. Distribution of mRNA expression showed sharp differences after acute vs. subchronic treatments for all transcripts. Subchronic ketamine induced an upergulation of D2R and DAT mRNA transcripts in the midbrain, since expression was significantly increased compared to both subchronic and acute vehicle-mediated expression.The observed molecular changes by acute vs. subchronic ketamine may model different steps in psychosis pathophysiology involving dopaminergic system.