When insulin is deficient , GLUT4 transporters are not inserted into the cell membranes , glucose is not transported into the cells and the blood glucose concentration increases.
Insulin deficiency provides more amino acid and glycerol substrates for glucose synthesis ie increased gluconeogenesis .
With a deficiency of insulin, there is both increased hepatic glucose production through increased glycogenolysis and gluconeogenesis as well as decreased glucose use. The result is hyperglycemia.
