Effects of malnutrition on microvillus membrane glucose transport and physical properties.

摘要: We examined sodium-dependent glucose transport, membrane lipid composition, and fluidity in microvillus vesicles isolated from the distal intestine of infant rabbits subjected to protein-energy malnutrition age-matched controls. In malnourished animals, transport was significantly enhanced, as evidenced by a twofold increase maximal capacity, Jmax. Carrier affinity for glucose, assessed Km process, unaffected. These alternations were associated with marked changes composition. Malnourished animals had an lipid-to-protein ratio membrane, which suggests that might be either reduction protein or lipid. This would expected membrane. However, we observed no differences static dynamic component fluidity, using multiple fluorescent probes, between dietary groups. Further analysis lipids undertaken establish whether quantitative subclasses could explain this discrepancy. found nutrient deprivation produced numerous alterations lipids. The major findings both cholesterol-to-phospholipid phosphatidylethanolamine-to-phosphatidylcholine ratios. Both decrease presumably represent compensatory response loss protein. Thus chronic postnatal initiates several adaptive responses include chemical composition resulting effect preserves efficient maintains physical properties