title: Dissociation of glomerular filtration and renal blood flow in HgCl2-induced acute renal failure.
abstract: This study evaluates the role of early renal vasoconstriction in the pathogenesis of mercuric chloride (HgCl2)-induced acute renal failure (ARF) in the dog. Within 3 hr after mercury, glomerular filtration rate (GFR), from 45 +/- 4 25 +/- 2 ml/min, and renal blood flow (RBF), from 268 +/- 22 to 161 +/- 19 ml/min, decreased simultaneously. A rise in diuresis and urinary solute excretion occurred. Morphological and functional studies excluded a major role for tubular leakage or obstruction. An attempt was made to prevent the early renal vasoconstriction, by the administration of Haemaccel, a plasma volume expander, alone or in combination with phentolamine. In both settings the fall in RBF after mercury was prevented. Haemaccel volume expansion alone provoked a significant rise in GFR before HgCl2, but the GFR fell by 29% 3 hr after HgCl2. The Haemaccel/phentolamine combination had no influence on pre-mercury GFR values. In this group, a decrease of GFR by 44% was noted 3 hr after mercury. In conclusion, changes in GFR and renal hemodynamics can be dissociated in the early phase of nephrotoxic ARF. The fall in GFR can be attributed either to a decrease in glomerular ultrafiltration capacity and/or changes in glomerular afferent and efferent resistances, leading to a decrease in glomerular hydrostatic pressure.
mesh_terms: D058186:Acute Kidney Injury / Q000139:chemically induced / Q000188:drug therapy / Q000503:physiopathology*; D000818:Animals; D004285:Dogs; D004359:Drug Therapy, Combination; D005919:Glomerular Filtration Rate / Q000187:drug effects; D007668:Kidney / Q000473:pathology / Q000648:ultrastructure; D008627:Mercuric Chloride; D008628:Mercury; D010646:Phentolamine / Q000008:administration & dosage / Q000627:therapeutic use; D011097:Polygeline / Q000008:administration & dosage / Q000627:therapeutic use; D012079:Renal Circulation / Q000187:drug effects
chemical_list: D008627:Mercuric Chloride; D011097:Polygeline; D008628:Mercury; D010646:Phentolamine