EXPRESSION OF MELANOCORTIN-1 RECEPTOR IN PERIAQUEDUCTAL GRAY-MATTER

THE localization of the melanocortin 1 (MC1) receptor in brain was inv estigated by in situ hybridization and immunohistochemistry. In rat pe riaqueductal gray matter (PAG), a small number of cells which displaye d a punctate distribution showed a specific hybridization signal for M C1 receptor mRNA, whereas other regions studied were negative. In huma n PAG, the immunoreactivity for MC1 receptor was detected in scattered cells. These results indicate that a restricted distribution of MC1 r eceptor is present in the central nervous system.