Differential basal proenkephalin gene expression in dorsal striatum and nucleus accumbens, and vulnerability to morphine self-administration in Fischer 344 and Lewis rats

1. Martín, S.
2. Manzanares, J.
3. Corchero, J.
4. García-Lecumberri, C.
5. Crespo, J.A.
6. Fuentes, J.A.
7. Ambrosio, E.