Sequential changes in intrarenal hemodynamics during saline infusion in the dog.
Intrarenal blood flow and volume (indicator-dilution technique), kidney volume (mercury-in-rubber resistance gage), intr-renal venous pressure, filtration fraction, and sodium excretion were determined dequentially before and during a l-h infusion of isotonicsaline 80 ml/kg in anesthetized dogs.  The cortical fraction of renal blood flow roseduring the first 20 min of infusion from an average of 70 to 77%, butreturned nearly to control levels during the last 20 min of infusion because ofa low rise in noncortical flow.  During the first 20 min a 23% increase in cortical blood volume accounted for one-third of the 8.5% increase in kidney volume, whereasin the last 20 min cortical blood volume had fallen nearly to control values and kidneyvolume was increased by 17.2%.  Intrarenal resistances calculated from intrarenalpressure and flow indicated persistent cortical prevenous dilatation, progressive cortical venous constriction, and only a slight late reduction in noncortical resistance. These data indicate that hemodynamics are shanging continuously during saline infusion and the natriuresis probably is multifactorial.
D000818:Animals; D001794:Blood Pressure; D004231:Diuresis; D004285:Dogs; D005260:Female; D005919:Glomerular Filtration Rate; D006439:Hemodynamics; D007552:Isotonic Solutions; D007668:Kidney / Q000098:blood supply*; D007672:Kidney Cortex / Q000098:blood supply; D008297:Male; D009318:Natriuresis; D012039:Regional Blood Flow; D012965:Sodium Chloride / Q000494:pharmacology; D013997:Time Factors; D014655:Vascular Resistance; D014690:Venous Pressure
D007552:Isotonic Solutions; D012965:Sodium Chloride