TROPHIC EFFECTS OF MELANOTROPIN-POTENTIATING FACTOR (MPF) ON CULTURESOF CELLS OF THE CENTRAL-NERVOUS-SYSTEM

MPF is a tetrapeptide (structure Lys-Lps-Gly-Glu) that elicits a varie ty of neurotrophic effects in vivo consistent with a role in neuronal regeneration. In support of this role, we now show that MPF stimulates the proliferation of cultured astrocytes and neurite outgrowth from c ultures of neocortical cholinergic and mesenchephalic dopaminergic neu rons. The dose-response relationships are biphasic (''bell shaped''), maximal responses being obtained with 10(-6) M concentrations of MPF. MPF and nerve growth factor seem to act on different receptors, becaus e their effects on cholinergic neurons are synergistic. (C) 1997 Elsev ier Science Inc.