Renal Handling of Salt and Water in the Early Stage of Obstructive Jaundice in Rabbits

Abstract

Renal handling of salt and water in the early stage of obstructive jaundice was studied in rabbits 10 days after the ligation of the common bile duct (BDL). Sham-operated (SO) animals served as controls. No sodium retention was found in BDL rabbits, despite reduced renal perfusion and elevated plasma aldosterone level. A redistribution of intrarenal blood flow was not found. The filtration fraction did not change. A saline load resulted in decreases in arterial hematocrit and total serum proteins, and increases in urine output, urinary sodium excretion and osmolal clearance. Blood pressure, glomerular filtration rate (GFR), RPF, the filtration fraction and the intrarenal flow distribution were not significantly affected by the saline load. No significant difference was found in the natriuretic response to the saline load between the BDL and SO groups. After 60 h of water deprivation, there was no significant difference in urine-to-plasma osmolality ratios or renal tissue fluid osmolality between the BDL and SO animals. The findings indicate that renal handling of salt and water was well maintained in the early phase of obstructive jaundice in rabbits. The data also suggest the critical role of the redistribution of intrarenal blood flow rather than of GFR or aldosterone in determining sodium retention in obstructive jaundice.

Reduced water and sodium intakes associated with high levels of natriuretic factor following common bile duct ligation in the rabbit

“…Renal function, sodium balance and plasma atrial natriuretic factor were determined on the fourth and tenth days after operation. Water intake and balance were lower in the OJ group both in thefirst study period (230 versus 519 mlldays 1-4, P < 0.001; and -2.4 versus 219 mlldays [1][2][3][4], P < 0.0001 respectively) and in the second study period (260 versus 865 mlldays 7-10, P < 0.0001; and I I versus 379 mlldays 7-10, P < 0.0001 respectively). Sodium intake was negligible in the OJ group both on day four (0.73 versus 7.15 m~/ 2 4 h, P <O.OOOI) and on day 10 (0.78 versus 15.78 m~/ 2 4 h, P <O.OOOl).…”