Basal magnocellular and pontine cholinergic neurons coexpress FGF receptor mRNA

By in situ hybridization histochemistry, fibroblast growth factor receptor gene (flg)-expressing neurons were newly identified in the basal magnocellular nuclei (the vertical and horizontal limbs of the diagonal band, and Meynert's nucleus). The present study also confirmed flg localization in the laterodorsal tegmental nucleus and the pedunculopontine tegmental nucleus of the pons. Immuno- and in situ hybridization histochemistry on the same sections demonstrated that choline acetyltransferase and flg were colocalized in single neurons of the diagonal band, Meynert's nucleus and the pontine tegmental areas. The results suggest that a significant number of the basal magnocellular and a majority of the mesopontine cholinergic neurons are directly affected by fibroblast growth factors (FGF) via FGF receptor gene.