What Students Need To Know About The Glomerular Filtration Rate and factors affecting GFR.

Owing to a shortage of kidneys for transplantation, the elderly and obese have begun to be accepted as kidney donors. After nephrectomy, the remaining kidney undergoes compensatory adaptation, and its total glomerular filtration rate (GFR) increases by 70% of the preoperative value within 8 to 12 weeks. Glomerular filtration rate (GFR) is the measure that describes the total amount of filtrate formed by all the renal corpuscles in both kidneys per minute. The glomerular filtration rate is directly proportional to the pressure gradient in the glomerulus, so changes in pressure will change GFR. GFR is also an indicator of urine production, increased GFR will increase urine production, and vice versa. The filtration constant is based on the surface area of the glomerular capillaries, and the hydrostatic pressure is a pushing force exerted from the flow of a fluid itself; osmotic pressure is the pulling force exerted by proteins. Changes in either the hydrostatic or osmotic pressure in the glomerulus or Bow