"In vitro" effect of GM1 ganglioside on adrenal chromaffin cells

Exposure of "in vitro" grown immature and adult adrenal chromaffin cells to concentrations of 10(-3) or 10(-5) M but not 10(-7) M GM1 ganglioside, resulted in significant increase in cell diameter, coupled with reduction of adhesion to substrate within 48 hrs of exposure. None of the GM1 concentrations, with or without serum supplementation, did significantly increase neuritogenesis in chromaffin cells. Immature chromaffin cells underwent neuritogenesis when grown in co-cultures with actively growing astroglia from striatum or cerebral cortex, an effect that was potentiated by NGF administration and blocked by anti-NGF. In neither of the former conditions did 10(-6) M GM1 prove to increase the number of neurite emitting cells nor their mean neuritic length further. It is speculated that GM1 does not perform the neuritogenic role described for central neurons in chromaffin cells, nor does it potentiate NGF effect on neuritogenesis observed in other peripheral neurons.