EXPRESSION OF GLIAL-CELL LINE-DERIVED NEUROTROPHIC FACTOR (GDNF) MESSENGER-RNA FOLLOWING MECHANICAL INJURY TO MOUSE STRIATUM

ALTHOUGH glial cell line-derived neurotrophic factor (GDNF) expression is low in the adult brain, its administration protects dopaminergic n eurons against a range of insults, leading to the suggestion of a role in dopaminergic regeneration. If locally produced GDNF is to fulfil a role in dopaminergic regeneration after injury, it seems reasonable t o hypothesize that its expression will increase after mechanical traum a. We have demonstrated that GDNF mRNA expression increases within 6 h of using a wire knife to injure adult mouse striatum. Expression doub les after 1 week and remains elevated for at least 1 month. Most GDNF expression is associated with haemosiderin-containing cells, indicatin g production by brain macrophages. GDNF production by macrophages may be essential for neural regeneration following CNS trauma.