Renal response to four hours of biliary obstruction in the dog

Abstract

Clearance studies were performed in anesthetized dogs before and 4 h after the acute obstruction of the common bile duct (ABDL). ABDL was not associated with any change in systemic hemodynamics or plasma volume. Glomerular filtration rate (GFR) rose by 15.3%, PAH [aminohipporate] clearance by 13.3%, and renal blood flow by 13% (all values significant at P < 0.05). Fractional excretion rates of water and Na rose from 0.29 to 1.1 and from 0.21 to 0.76%, respectively (P < 0.05). These changes in renal function were associated with a failure of bile excretion rather than distension of the biliary tree or failure of bile to enter the duodenum. They did not depend on intact hepatic nerves, alteration of hepatic perfusion, or the release of gastrointestinal vasoactive peptides. The increment in renal perfusion was maintained for 2-3 days before returning to baseline levels. Several lines of evidence suggested that factors influencing the renal tubule and the renal microcirculation might be separate in nature: e.g., urinary Na excretion (UNaV) could increase without a change in GFR; if ABDL was relieved, .DELTA.UNaV and .DELTA.GFR returned to base line with different time courses; and controlling perfusion to the left kidney during ABDL reduced but did not abolish the increase in UNaV. Both effects could be transferred to recipient dogs by cross-perfusion. Four hours of ABDL may significantly influence renal function through the appearance of humoral factors in the circulation.