ABSTRACT
Glomerular filtration rate is only one of the several markers that describe renal performance. Renal blood flow, tubular functions involved in protein and electrolyte reabsorption and secretion of xenobiotics, are critical and relevant parameters when considering kidney exocrine function. Moreover, kidneys are endocrine organs involved in the long-term regulation of blood pressure by the secretion of renin and other components of the renin-angiotensin system, such as control of erythropoiesis by erythropoietin, and of phosphate and calcium metabolism by vitamin D hydroxylation.
