Amphetamine increases tyrosine kinase-B receptor expression in the dorsal striatum.

Neurotrophic signaling is thought to be important for neuroplasticity in certain forebrain regions following psychostimulant exposure. In this study, we found that repeated administration of amphetamine (5 mg/kg, once daily, 5 days) to rats significantly increased tyrosine kinase-B receptor mRNA levels in the striatum, ventral bed nucleus, and piriform cortex. The most robust increase in tyrosine kinase-B expression occurred in dorsal aspects of the striatum, which also showed elevated levels after a single amphetamine injection. These findings indicate that changes in striatal tyrosine kinase-B signaling could play a role in neuroadaptations and behavioral changes induced by amphetamine treatment.