TROPHIC EFFECT OF ERYTHROPOIETIN AND OTHER HEMATOPOIETIC FACTORS ON CENTRAL CHOLINERGIC NEURONS INVITRO AND INVIVO

In vitro granulocyte colony-stimulating factor (G-CSF), macrophage col ony-stimulating factor (M-CSF), erythropoietin (EPO), and erythroid di fferentiation factor (EDF) augmented choline acetyltransferase (ChAT) activity in mouse embryonic primary septal neurons and in cholinergic hybridoma cell line, SN6.10.2.2. This is similar to the effects seen w ith interleukin-3 (IL-3) or granulocyte-macrophage colony-stimulating factor (GM-CSF). Moreover, in vivo GM-CSF and EPO promoted survival of septal cholinergic neurons in adult rats which had undergone fimbria- fornix transections. These results suggest that some of the hematopoie tic factors act on cholinergic neurons as 'neurotrophic factors' to in fluence the differentiation, maintenance and regeneration of these neu rons.