Effects of chronic alcohol consumption in weanling rats on brain gangliosides

Chronic ingestion of ethyl alcohol in pre-weanling rats can decrease whole-brain levels of sialic acid (SA), an acidic sugar that serves as terminal groups on glycolipids (gangliosides) and glycoproteins. Because SA occurs in both classes of membrane-bound chemicals, the alcohol effect could be on either or both parent compounds. We examined the effects of alcohol on gangliosides by measuring levels of six specific ganglioside species in post-weanling rats that were fed liquid alcohol diet for 35 days. We found no major effect on any of the ganglioside species in the alcohol-fed rats compared with their pair-fed littermates. These data suggest that alcohol may have acute effects on membrane gangliosides, but during chronic exposure in more mature animals, the membrane may adapt and maintain near-normal ganglioside composition. Thus, gangliosides may reflect mechanisms of membrane tolerance; they could also be involved in mediating metabolic dependencies in neuronal membranes, a possibility that needs testing.