Effects of Albumin and Mannitol on Blood Flow Autoregulation in Isolated Dog Kidneys

Abstract

In isolated blood-perfused dog kidneys, additions of bovine serum albumin abolished blood flow autoregulation. Replacing the perfusate with fresh blood or adding mannitol restored autoregulation. When mannitol alone was added, autoregulation also decreased, but less than with albumin alone, and subsequent addition of albumin abolished autoregulation. Diminished distal water and electrolyte delivery, subcapsular renal pressure, and vascular reactivity to angiotensin II occurred with albumin addition. Mannitol ameliorates the effect of albumin on autoregulation by increasing intrarenal tissue pressure and distal delivery.