Chromium-51 ethylenediaminetetraacetate for estimation of globerular filtration rate.

Renal clearances of inulin and chromium-51 ethylenediaminetetraacetate were compared in sheep. In 41 clearance periods from five animals the mean clearance ratio of the chelate to inulin was 0.95 +/- 0.03 (S.D.). Part of the difference between the two sets of results may have been due to binding of the metal chelate by plasma protein since 1.5 to 2 percent of chromium-51 ethylenediaminetetraacetate in plasma could not be removed by dialysis.