title: Complement and leukocyte independent proteinuria and eicosanoid synthesis in rat membranous nephropathy.
abstract: We examined the effect of complement depletion and leukocyte depletion on an experimental model of membranous nephropathy. Nephrosis was induced in 200-gm male Sprague-Dawley rats by priming with cationic bovine gamma-globulin in adjuvant on day 1 followed by intravenous challenge with antigen starting on day 10. No naive control rats had immunofluorescent deposits in glomeruli; urine protein was less than 10 mg/24 hour and glomerular thromboxane synthesis was 658 +/- 64 ng/mg glomerular dry weight. In contrast, all rats primed and challenged with cationic bovine gamma-globulin had intense granular capillary wall deposits of rats IgG, bovine gamma-globulin, C3 and C5; severe proteinuria (183 +/- 24 mg/24 hour) was observed, associated with a 3-fold increase in glomerular thromboxane (2,393 +/- 574 ng/mg, all p less than 0.01 versus naive controls). In some rats, administration of cobra venom factor and antiserum to rat C3, starting on day 8 was used to deplete complement; hemolytic C3 and C5 were less than 2% of normal at sacrifice. These rats had IgG and bovine gamma-globulin deposits, whereas they lacked glomerular C3 or C5. Proteinuria (209 +/- 28 mg/24 hour) and glomerular thromboxane (2,087 +/- 394 ng/mg) were markedly increased compared with control, but no different from normocomplementemic rats primed and challenged with cationic bovine gamma-globulin. In other rats, depletion of leukocytes was achieved by 1,000 R x-irradiation on day 7; at sacrifice, irradiated rats had 1,270 +/- 462 wbc/microliter versus 10,375 +/- 1,652 in nephrotic rats given no other treatment, with unaltered differentials. These rats had glomerular deposits of rat IgG, bovine gamma-globulin, C3 and C5 indistinguishable from nephrotic rats with normal leukocyte counts in intensity and distribution. Proteinuria (202 +/- 30) and glomerular thromboxane (2,358 +/- 189 ng/mg) were markedly elevated compared with naive controls, but were not different from the normocomplementemic or complement-depleted groups primed and challenged with antigen. An additional control group included rats primed with ovalbumin on day 1, irradiated with 1,000 R on day 7, and challenged with cationic bovine gamma-globulin starting on day 10. This group had granular capillary wall deposits of bovine gamma-globulin, but not deposits of IgG, C3, or C5; urine protein excretion (less than 10 mg/24 hours) and glomerular thromboxane synthesis (613 +/- 90) were not different from naive controls. Glomerular prostaglandin E2 synthesis did not differ among the five groups.(ABSTRACT TRUNCATED AT 400 WORDS)
mesh_terms: D000818:Animals; D003176:Complement C3 / Q000378:metabolism; D003182:Complement C5 / Q000378:metabolism; D003165:Complement System Proteins / Q000378:metabolism*; D004195:Disease Models, Animal; D005455:Fluorescent Antibody Technique; D015433:Glomerulonephritis, Membranous / Q000150:complications / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D007958:Leukocyte Count; D007962:Leukocytes / Q000378:metabolism*; D008297:Male; D011453:Prostaglandins / Q000032:analysis / Q000096:biosynthesis; D011507:Proteinuria / Q000209:etiology*; D051381:Rats; D011919:Rats, Inbred Strains; D013931:Thromboxanes / Q000032:analysis / Q000096:biosynthesis*
chemical_list: D003176:Complement C3; D003182:Complement C5; D011453:Prostaglandins; D013931:Thromboxanes; D003165:Complement System Proteins