6-OHDA denervation substantially decreases DCC mRNA levels in rat substantia nigra compacta

THE function of deleted in colorectal cancer (DCC) protein, a member of the immunoglobulin superfamily of cell adhesion molecules, in the adult CNS is unknown. Recently the transcript encoding DCC has been shown to be express ed in a variety of rat brain regions, including the substantia nigra pars c ompacta and the striatum, which encompasses the nigrostriatal dopaminergic system. In the present study DCC mRNA expression in substantia nigra, stria tum, dentate gyrus and piriform cortex was investigated in adult rats using in situ hybridization histochemistry following unilateral injections of 6- hydroxydopamine (6-OHDA) in the median forebrain bundle. DCC mRNA levels we re greatly reduced in the substantia nigra ipsilateral to the 6-OHDA lesion compared to those on the contralateral side while there was no apparent ef fect on DCC mRNA levels in the other regions analysed. These data indicate expression of DCC mRNA in dopamine neurones of the substantia nigra pars co mpacta and support a role for DCC in the adult CNS, with potential involvem ent in the function of central dopamine neurones. NeuroReport 9: 3553-3556 (C) 1998 Lippincott Williams & Wilkins.