Summary of principal findings
| METH SA increases NT levels in basal ganglia structures with the effect generally being greater in the SAM versus YM animals. |
| In contrast to METH SA, extinction of lever pressing for METH correlates with a decrease in most basal ganglia structures (except substantia nigra) with the best correlation in the anterior, closely followed by the posterior, dorsal striatum. The extinction-induced decreases in NT levels were generally greatest in the SAM versus YM rats. |
| Similar to METH SA, extinction of lever pressing for food SA also correlated with NT decreases in both anterior and posterior dorsal striatum, but not globus pallidus or the substantia nigra. |
| Results suggest that activation of D2 receptors contribute to the basal ganglia NT response to extinction of METH SA, while previous studies demonstrated that activation of D1 receptors contribute to NT responses to METH SA itself (Frankel et al., 2011). |
| Activation of NTR1 receptors appears to contribute to the reduction in lever pressing associated with extinction of METH SA. |