MODULATION OF ETHANOL NEUROTOXICITY BY NERVE GROWTH-FACTOR

Dorsal root ganglion (DRG) neurons were cultured with varying concentr ations of ethanol and NGF. At low concentrations of NGF (0.1 ng/ml) mo derate initial ethanol levels (250 mg/dl) significantly suppressed neu rite outgrowth. Higher NGF concentrations (5 ng/ml) protected against this neurotoxicity. At this higher NGF concentration, neuronal surviva l was not significantly affected by exposure to 0.25-4 g/dl ethanol, a lthough survival was significantly diminished at 5 and 6 g/dl. Neurite outgrowth was a more sensitive indicator of ethanol neurotoxicity in this population, with significant decreases in process extension seen with 1 g/dl ethanol. When cultures were supplemented with 10 ng/ml NGF , however, process elaboration was significantly greater at 1 g/dl eth anol than that measured with 5 ng/ml NGF, and in fact did not differ f rom NGF controls. These studies indicate that NGF can provide neuropro tective effects against ethanol toxicity under these conditions. The r esults are discussed in relation to other recent reports of trophic fa ctor neuroprotection.