Why does the pancreatic beta-cell glucose uptake rate decrease during prolonged insulin resistance, even with elevated blood glucose?

💡 Explanation

Pancreatic beta-cells primarily use GLUT2 for glucose uptake under normal conditions, but insulin resistance impairs the translocation of GLUT4, usually present at lower levels but crucial for insulin-stimulated glucose uptake. Because of this impaired translocation, the glucose uptake decreases despite GLUT2 presence, therefore reduced glucose stimulates insulin secretion, rather than saturation of glycolysis.

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