Renal physiology diabetes mellitus

The filtration coefficient is determined by the surface area and permeability of the filtration barrier. An increase in the filtration coefficient leads to an increase in GFR if the filtration coefficient decreases, then GFR decreases. However, this factor does not play a role in the daily regulation of GFR because its value is relatively constant under normal physiological conditions. On the other hand, chronic, uncontrolled hypertension and diabetes mellitus lead to gradual thickening of the basement membrane and therefore to a decrease in the filtration coefficient and GFR, and impaired renal function. 

---