Use of hydrogen gas clearance for measurement of renal circulation. An experimental study

Inhalation of hydrogen gas and its immediate diffusion into the blood permits an accurate and reproducible determination of its clearance through a fine platinum electrode inserted in the renal cortex. The oxidation of molecular hydrogen at the surface of the electrode generates a current which is then easily recorded. Such recordings accurately reflect regional arterial circulation. Experiments have been done in rats to determine regional renal cortical arterial circulation in (1) normal conditions, (2) immediately following unilateral, complete ureteral obstruction, and (3) following a twenty-four-hour ureteral obstruction. Hundreds of simple and reproducible recordings were obtained. Although acute obstruction does not immediately affect cortical blood supply, a twenty-four-hour obstruction was accompanied by a 31.3 per cent reduction in circulation.