Measurement of intrarenal anatomic distribution of krypton-85 in endotoxic shock in dogs

Abstract

Renal blood flow distribution was measured in control dogs and dogs in endotoxic shock by utilizing a modification of 85Kr washout. Kidneys, injected with 85Kr via a renal arterial cannula, were removed at several specific intervals after injection, rapidly frozen, and sectioned transversely so that pieces of tissue could be isolated and counted for radioactivity. Control outer cortical blood flow was 462 ml/min per 100 g tissue wt, but 122 ml/min per 100 g during shock. Control inner cortical outer medullary flow was 396 ml/min per 100 g, but 166 ml/min per 100 g in shock. Control flow in the inner stripe of the outer zone of the medulla was 130 ml/min per 100 g and 134 ml/min per 100 g in shock. In shock the initial volume of radioactivity distributed to outer cortex was smaller, to inner cortex the same, and to inner stripe outer zone of the medulla larger than in controls. This study delineates renal washout of 85Kr from specific areas of the kidney and indicates the alterations in extent and magnitude of this washout in endotoxic shock.