In sharp contrast, liver glycogen content remained significantly high in the liver of N3U + GN neonates (Fig. 7A) and no variation in serum glucose values was observed in response to exogenous administration of glucagon indicating that the lack of glycogen mobilization in U hepatocytes was not only due to the very low levels of circulating glucagon (Fig. 7B). Here, GCG is linked to ganglioneuroma.