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Biomedical subjects

F Thaiss

Publications and source records attributed to F Thaiss.

At least 19 recordsLinked to original sources
PubMed1992

Increased oxygen radical and eicosanoid formation in immune-mediated mesangial cell injury.

To evaluate whether monocytes/macrophages derived from glomeruli could be a source of increased eicosanoid and free oxygen radical formation in glomerular disease, monocytes/macrophage (M/M) were isolated from nephritic glomeruli and their in vitro generation of eicosanoids and superoxides were measured. Glomerular immune injury was induced by i.v. injection of a rabbit-anti-rat thymocyte antiserum (ATS). Kidneys were removed two, five, and 24 hours, and three and eight days after ATS. Adhesive glomerular macrophages were obtained by isolation of glomeruli, enzymatic digestion and incubation of the single cell suspensions in culture dishes. O2-production was evaluated by superoxide dismutase (SOD)-inhibitable reduction of ferricytochrome C; PGE2 and TxB2 release was assessed by direct RIA. Glomerular macrophage infiltration was maximal 24 hours after intravenous antibody (35.9 +/- 5.1 M/M per glomerulus). In vitro production of superoxide was significantly enhanced (P less than 0.001) five hours after ATS administration (51.6 +/- 4.4 nmol O2/10(6) MM/hr), when compared with M/M from controls (30.4 +/- 2.0 nmol O2/10(6) MM/hr). TxB2 formation of glomerular M/M was increased (P less than 0.001) two hours and five hours after ATS administration (1056 +/- 75 and 1182 +/- 112 pg TxB2/10(6) MM/hr) compared with controls (390 +/- 34 pg TxB2/10(6) MM/hr). PGE2 synthesis, however, was decreased (P less than 0.01) at five hours after ATS (629 +/- 43 pg PGE2/10(6) MM/hr) compared with controls (950 +/- 125 pg PGE2/10(6) MM/hr). Furthermore, there was release of leukotriene B4 (LTB4) in monocytes of nephritic glomeruli five hours after ATS administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Thromboxane mediates glomerular haemodynamics in a model of chronic glomerular disease.

In order to evaluate a possible haemodynamic role of cyclooxygenase products in chronic renal disease, a model of chronic glomerular injury was induced in nephritic rats by unilateral nephrectomy and high dietary protein intake. Eight weeks after induction of an in situ immune complex glomerulonephritis (CGN), rats subjected to high protein (HP) intake (42% protein) and uninephrectomy revealed a significantly lower glomerular filtration rate (GFR; 485 +/- 53 microliters min-1 100 g-1 body weight (BW)) compared with uninephrectomized rats with ICGN which were on low protein (LP) diet (6% protein) (825 +/- 155 microliters min-1 100 g-1 BW) (P less than 0.01). The glomerular thromboxane B2 (TxB2) formation in uninephrectomized rats with ICGN on either LP or HP intake was not significantly different (HP: 473 +/- 61; LP: 493 +/- 63 pg mg-1 min-1), but was significantly higher when compared with non-nephritic controls on either diet. Glomerular prostaglandin E2 (PGE2) production in rats on HP diet was higher compared with rats with LP intake (HP: 617 +/- 67; LP: 351 +/- 76 pg mg-1 min-1) (P less than 0.01). The thromboxane receptor blocker daltroban significantly elevated suppressed GFR in ICGN rats on HP diet (ICGN+vehicle: 426 +/- 69; ICGN+daltro: 689 +/- 66 microliters min-1 100 g-1 BW) (P less than 0.01). Thromboxane receptor blockade had no effect on glomerular haemodynamics in ICGN animals receiving LP diet (ICGN+vehicle: 771 +/- 24; ICGN+daltro: 684 +/- 85 microliters min-1 100 g-1 BW).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Morphologic and functional consequences of immune-mediated mesangiolysis: development of chronic glomerular sclerosis.

The i.v. injection of a rabbit anti-rat thymocyte serum (ATS) induces mesangiolysis in rats, followed by a mesangioproliferative glomerulonephritis (4 to 7 days after antibody). This proliferative lesion disappears 4 to 6 wks after antibody. In order to induce an antibody-mediated sclerotic glomerular disease, uninephrectomized rats received ATS twice at 6-wk interval. At 6 months after the first antibody injection, albuminuria, arterial blood pressure, and inulin clearances were evaluated and renal morphologic studies were performed. At the time of evaluation, mean arterial blood pressure and inulin clearances were not different between animals that received the antibody and uninephrectomized controls. Rats that were injected with antibody, however, had significantly higher albuminuria compared with that of controls. Glomeruli of rats with ATS revealed expansion of the glomerular mesangial matrix and focal sclerosis. A semiquantitative morphologic analysis revealed an increased incidence of glomerular lesions and a higher glomerular damage index in kidneys of nephritic rats. These data demonstrate that the repetitive injection of ATS to unilaterally nephrectomized rats induces a model of chronic glomerular sclerosis.

Albuminuria↗
PubMed1992

A rat model of progressive chronic glomerular sclerosis: the role of thromboxane inhibition.

In order to evaluate a possible role of thromboxane A2 (TxA2) in the pathophysiology of chronic glomerular disease, we studied the effect of a 12-wk combined treatment with the thromboxane receptor blocker Daltroban (D) and the thromboxane synthesis inhibitor UK 38485 (UK) on glomerular function and morphology in a rat model of chronic progressive glomerular injury. The glomerular lesion was induced in unilaterally nephrectomized rats by the repeated i.v. injection of an antibody directed against mesangial cells. Control rats were uninephrectomized. Three months after the first antibody injection before D and UK treatment, albuminuria (35.8 +/- 3.6 mg/24 h) and glomerular TxB2 formation (146 +/- 20 pg/mg of protein/min) were significantly higher compared with control values (albuminuria, 14.3 +/- 3.5 mg/24 h; TxB2, 59 +/- 16 pg/mg/min). Six months after antibody, albuminuria in nephritic rats had increased to 135 +/- 17 mg/24 h. In nephritic rats treated with D plus UK, albuminuria (44 +/- 12 mg/24 h), however, was significantly (P less than 0.001) inhibited. Quantitative morphological analysis (glomerular damage index) 6 months after antibody revealed significantly (P less than 0.001) increased glomerular lesions in nephritic rats (0.353 +/- 0.095) compared with that in uninephrectomized controls (0.045 +/- 0.014). The treatment of rats with D and UK significantly (P less than 0.001) reduced the glomerular damage index (0.101 +/- 0.004) in nephritic rats. D plus UK treatment reduced glomerular TxB2 formation but increased prostaglandin E2 and 6-keto prostaglandin F1 alpha release by isolated glomeruli. This study demonstrates that interventional treatment with D and UK ameliorates albuminuria and glomerular morphological lesions in a rat model of immunologically induced progressive glomerular injury.

Albuminuria↗
PubMed1992

Angiotensin II-induced proliferation of cultured murine mesangial cells: inhibitory role of atrial natriuretic peptide.

Angiotensin II (ANG II), as a single factor, induces proliferation in a cultured murine mesangial cell line (MMC). This study was undertaken to evaluate a possible influence of atrial natriuretic peptide (ANP) on this ANG II-induced proliferation. ANP (10(-7) M) for 2 min significantly increased intracellular cGMP levels in MMC. This increase in cGMP was totally abolished when cells were preincubated for 5 min with 10(-7) M ANG II. Stimulation of intracellular cGMP formation by sodium nitroprusside was also decreased in the presence of ANG II. The ANG II-mediated inhibition of ANP-stimulated intracellular cGMP levels was blocked by Dupont 753, suggesting signal transduction through ANG II receptors of the AT1 class. ANP (10(-7) M) for 24 h completely abolished the ANG II-induced proliferation in MMC. However, 10(-7) M ANP had no significant effect on mitogenesis induced by platelet-derived growth factor or epidermal growth factor. Furthermore, ANP reduced the ANG II-stimulated expression of the proliferating cell nuclear antigen, a cofactor of polymerase delta that is active in the S-phase of the cell cycle. The addition of 10(-3) M N-monobutyryl-guanosine 3':5'-cyclic monophosphate or 8-bromo-guanosine 3':5'-cyclic monophosphate also blocked the ANG II-induced proliferation. ANP (10(-7)) M for 24 h had no significant influence on the expression (number and dissociation constant) of ANG II receptors as determined by binding assays. These results suggest that, besides the previously shown vasoconstrictive and vasodilating effects, complex interactions between ANG II and ANP exist that can modulate mesangial cell growth.(ABSTRACT TRUNCATED AT 250 WORDS)

Angiotensin II↗
PubMed1991

The platelet activating factor receptor antagonist WEB 2170 improves glomerular hemodynamics and morphology in a proliferative model of mesangial cell injury.

Rats were treated with the platelet activating factor receptor antagonist WEB 2170 (15 mg/kg/day) in three different protocols to evaluate a possible role of platelet activating factor in an experimental proliferative model of glomerular disease. The glomerular immune injury was initiated by the i.v. administration of a rabbit anti-rat thymocyte antiserum. Anti-rat thymocyte antiserum induces a proliferative glomerulonephritis with reduction of glomerular filtration rate (614 +/- 94) compared with controls (1,120 +/- 192 microL/min/100 g body wt) when studied at day 7. Treatment of rats with WEB 2170 over 8 days (starting at day -1; protocol 1) ameliorated the loss in glomerular filtration rate (936 +/- 82 microL/min/100 g body wt) in nephritic rats at day 7; however, it had no effect on controls (1,142 +/- 104 microL/min/100 g body wt). Interventional treatment with WEB 2170 (starting at day 4 after anti-rat thymocyte antiserum; protocol 2) also improved glomerular function when glomerular filtration rate was already reduced (410 +/- 41 microL/min/100 g body wt) at day 4. The platelet activating factor receptor antagonist given at day 7 after induction of disease (protocol 3) did not improve impaired glomerular filtration rate. Preinterventional and interventional treatment with WEB 2170 reduced the infiltration of polymorphonuclear granulocytes in glomeruli. Interventional treatment with WEB 2170 also reduced glomerular morphologic damage in nephritic glomeruli. The data demonstrate a beneficial effect of the platelet activating factor receptor antagonist in this animal model of proliferative glomerulonephritis which suggests that platelet activating factor might play an important role in the mediation of this disease.

Animals↗
PubMed1990

Immune-mediated mesangial cell injury--biosynthesis and function of prostanoids.

We studied the formation of cyclo-oxygenase products in a rat model of mesangial cell injury, in order to determine a possible role of prostaglandin E2 (PGE2), prostaglandin I2 (determined as 6-keto-PGF1 alpha and thromboxane A2 (TxA2) in immune-mediated glomerular disease. Selective immune-mediated mesangial cell injury was induced by i.v. administration of a rabbit anti-rat thymocyte antiserum (ATS). Intravenous ATS leads to immune deposits in the mesangium followed by mesangiolysis and the infiltration of polymorphonuclear granulocytes and monocytes. Glomerular TxB2 formation two hours (292 +/- 27 pg/mg/min) and 48 hours (396 +/- 69 pg/mg/min) following antibody was significantly (P less than 0.05) higher compared to animals receiving non-antibody rabbit IgG (TxB2: 2 hr 143 +/- 13; 48 hr 171 +/- 32 pg/mg/min). Treatment with cobra venom factor (CVF) and the reduction of glomerular monocyte infiltration inhibited the increase of glomerular TxB2 formation significantly. Depletion of granulocytes with a rabbit anti-rat granulocyte serum had no effect on glomerular prostanoid formation following ATS. Glomerular PGE2 and 6-keto PGF1 alpha production was not altered following ATS. Inulin clearance in rats with immune-mediated mesangial cell injury was significantly (P less than 0.001) lower at two hours (456 +/- 24 microliters/min/100 g body wt) and 48 hours (433 +/- 54 microliters/min/100 g body wt) compared to their corresponding control animals which were treated with non-antibody IgG (2 hr: 914 +/- 51; 48 hr: 694 +/- 79 microliters/min/100 g body wt).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Glomerular angiotensinase A in the rat: increase of enzyme activity following renal ablation.

Angiotensinase A (aminopeptidase A; ATA) is an angiotensin II splitting exopeptidase, which is localized in endothelial and epithelial cells of the glomerular tuft. In order to investigate the influence of a reduction in renal mass on enzyme activity, ATA activity was measured in isolated rat glomeruli five and 14 weeks after 1-1/3 nephrectomy. Glomerular ATA activity in remnant kidneys increased significantly after five weeks following ablation compared with glomeruli of two kidney control rats (5.34 +/- 4.02 vs. 1.71 +/- 1.96 mU/mg protein, P less than 0.05). After 14 weeks, however, this difference was no longer present. Treatment of rats with enalapril or saralasin inhibited the increase of ATA seen five weeks after renal ablation, whereas indomethacin had no effect on enzyme activity. Furthermore, normal two kidney rats, treated with furosemide, revealed a higher glomerular ATA than two kidney controls (5.5 +/- 2.64 vs. 2.1 +/- 1.7 mU/mg protein, P less than 0.05). In vitro superfusion of isolated glomeruli with enalaprilate or furosemide from rats after renal ablation did not influence enzyme activity, however, superfusion with 0.05 mM angiotensin II or 0.05 mM saralasin significantly reduced ATA. Our results suggest that glomerular ATA might be involved in the early regulation of the intrarenal renin-angiotensin system and could modify glomerular adaptation to reduce renal mass by affecting angiotensin II degradation.

Adaptation, Physiological↗
PubMed1990

Cyclooxygenase inhibition enhances rat interleukin 1 beta-induced growth of rat mesangial cells in culture.

The cytokine interleukin 1 (IL-1) has growth-promoting activities on mesangial cells (MC) and enhances MC prostanoid formation. A possible role of endogenous cyclooxygenase products on IL-1-mediated growth of MC is, however, unknown. Therefore we evaluated the effect of cyclooxygenase inhibition on growth of mesangial cells in culture, which were exposed to DNA recombinant rat interleukin 1 beta (rIL-1 beta). rIL-1 beta increased [3H]thymidine uptake in MC by approximately 70% after 48 h. This growth-promoting activity of the cytokine was observed at 1 ng/ml and was not further enhanced by the increase of the IL-1 beta concentration less than or equal to 100-fold. IL-1 beta, however, dose dependently stimulated prostaglandin E2 (PGE2) formation by MC. When prostaglandin synthesis was inhibited by indomethacin (Indo, 1 microgram/ml), rIL-1 beta (10 ng/ml)-induced cell proliferation was sevenfold greater compared with rIL-1 beta alone. In the presence of Indo (1 microgram/ml), rIL-1 beta (1, 10, 50, and 100 ng/ml) dose dependently stimulated MC proliferation. The addition of exogenous PGE2 (10(-7) and 10(-8) M) to Indo-treated MC blocked the mitogenic response of IL-1 beta. We conclude that endogenous PGE2 formation, which is stimulated by IL-1 beta, antagonizes the growth-promoting activity of the cytokine. PGE2 may thus exert antiproliferative effects in glomerular diseases, whereas IL-1 might mediate cell growth.

Animals↗
PubMed1990

Dietary fish oil intake: effects on glomerular prostanoid formation, hemodynamics, and proteinuria in nephrotoxic serum nephritis.

Dietary fish oil intake improves glomerular pathology and proteinuria in murine models of autoimmune disease. We evaluated glomerular prostanoid formation, glomerular hemodynamics, and proteinuria in rats with nephrotoxic serum nephritis (NSN) to test whether this beneficial effect of marine lipids also applies to other animal models of glomerular immune injury. Rats were fed diets (8 weeks) containing either cod liver oil or sunflower oil. NSN was induced with a rabbit anti-rat glomerular basement membrane antiserum. Antibody injection significantly stimulated glomerular thromboxane B2 (TxB2) formation in animals fed cod liver oil and sunflower oil at 2 hours, 24 hours, and 7 days. TxB2 production in glomeruli of sunflower oil rats, however, was five to seven times higher when compared with that in rats fed cod liver oil. The dietary regimen led to a significant decrease of glomerular TxB2 and prostaglandin E2 formation in the animals receiving cod liver oil when compared with those fed sunflower oil. Induction of NSN resulted in a significant fall of inulin clearance (Cin) and paraaminohippurate clearance at 2 hours, 24 hours, and 7 days in both groups. The decrease in Cin at 2 hours was greater in rats fed cod liver oil when compared with animals receiving sunflower oil (p less than 0.02); it was not different, however, at 24 hours and 7 days. Animals with NSN developed proteinuria. There was no difference in protein excretion between rats fed cod liver oil or those fed sunflower oil (days 2 and 7).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Effect of cyclosporin A on carbohydrate metabolism in the rat.

Liver and kidney carbohydrate metabolism was investigated in rats treated with daily doses of 15 mg/kg body weight cyclosporin A (CyA) for 2 and 8 weeks or of 50 mg/kg body weight CyA for 2 weeks. The higher dosage caused significantly reduced liver glycogen and liver glycogen synthetase activity (of both active I-form and total enzyme activity), whereas the activity of the glycogen-degrading enzyme phosphorylase (active a-form and total activity) remained unchanged. Plasma glucose and glucagon levels, as well as blood ketone bodies of these animals, increased significantly and plasma insulin decreased. In contrast, kidney glycogen and glucose content were higher in rats treated with 50 mg CyA, probably due to enhanced ketone body utilization. Reduced liver glycogen synthetase activity was also found in rats treated with 15 mg CyA. Our data suggest that hypoinsulinemia, induced by CyA, might be a contributing factor to the hyperglycemia, which is mainly due to inhibition of liver glycogen synthesis.

Animals↗
PubMed1989

Ultrastructural studies in passive in situ immune complex glomerulonephritis. A rat model for membranous glomerulonephritis.

Morphologic studies were performed in a passive model of in situ immune complex glomerulonephritis in rats. The formation and fate of subepithelial immune complexes as well as the role of glomerular polyanion in the induction of disease were examined. Unilateral in situ immune complex glomerulonephritis was induced in rats by perfusion of cationised horse spleen ferritin (pI greater than 9.5) (400 micrograms/rat) into the left kidney followed by systemic injection of 0.2 ml (= 400 micrograms precipitating antibody) of sheep anti-ferritin antiserum 2 h later. This schedule induced glomerulonephritis with proteinuria (mean maximum 100 mg/24 h between the 5th and the 12th day). Rats were sacrificed at intervals between 1 h and 42 days after induction of glomerulonephritis, samples of renal tissue were examined by light, immunofluorescence and electron microscopy (including staining of anionic sites by polyethyleneimine). The lesion induced closely resembled that of membranous glomerulonephritis in man as massive subepithelial deposits were seen with very little cellular infiltration or proliferation. The antigen (ferritin) deposits were initially located subepithelially; from 2 weeks onwards intramembranous deposits in the thickened basement membrane were present, the apparent translocation being due to excessive newly synthesised basement membrane material which encloses the deposits. A loss of anionic sites in the lamina rara interna, lamina rara externa and on the epithelial cell surface coat preceded the development of proteinuria.

Animals↗
PubMed1989

Effect of thromboxane synthesis inhibition in a model of membranous nephropathy.

The effect of the thromboxane synthesis inhibitor UK 38485 on glomerular filtration rate (GFR) and proteinuria was evaluated in a rat model of unilateral membranous nephropathy. Two and 24 hours following perfusion of kidneys with cationized human IgG and i.v. administration of anti-human IgG-antiserum (in situ ICGN), glomerular thromboxane B2 (TxB2) formation was significantly higher (2 hr: 448 +/- 116 pg/mg protein/min; 24 hr: 173 +/- 21 pg/mg protein/min) compared to control (C) kidneys (2 hr: 173 +/- 21 pg/mg protein/min, P less than 0.005; 24 hr: 154 +/- 17 pg/mg protein/min, P less than 0.025). Two and seven days after induction of ICGN these differences were no longer present. Pretreatment with the thromboxane synthesis inhibitor UK 38485 prevented the decrease in GFR, which occurred two hours after induction of the glomerular disease (without UK: 161 +/- 31; with UK 325 +/- 21 microliters/100 g body wt/min). This UK 38485 effect on GFR was no longer detectable at 24 hours, two days and seven days. Initiation of glomerular immune injury was followed by significant proteinuria which averaged 250 +/- 85 mg/24 hr at day two. UK 38485 treatment, which reduced TxB2 formation in isolated glomeruli by 90% did not influence proteinuria. These data demonstrate that induction of heterologous, in situ immune complex glomerulonephritis stimulates glomerular thromboxane B2 formation, an effect which partially modulates the decrease in GFR at two hours. Thromboxane, however, does not seem to play a role in the mediation of proteinuria in this animal model.

Animals↗
PubMed1989

Cyclosporin A prevents proteinuria in an active model of membranous nephropathy in rats.

The effect of the immunosuppressant Cyclosporin A on an active model of in situ immune complex glomerulonephritis was evaluated. Wistar rats were preimmunized with human IgG and 2 weeks after the last antigen injection, the left kidney was perfused with cationized human IgG in order to induce unilateral in situ immune complex glomerulonephritis. Three groups of rats were treated orally with Cyclosporin A (15 mg/kg body weight/day) beginning 2 days before induction of disease and continuing for 7 or 14 days afterwards, or alternatively treatment was commenced 5 days after induction of disease and continued until day 14. Cyclosporin A significantly reduced proteinuria (40 +/- 7 mg/day) in rats with immune complex glomerulonephritis when compared with untreated nephritic controls (250 +/- 65 mg/day). This effect was observed when rats were pretreated with Cyclosporin A and even when the drug was given in established disease, 5 days after induction. Proteinuria appeared in rats pretreated with Cyclosporin A when drug administration was stopped at day 7. Cyclosporin A did not alter immune complex formation in glomeruli or serum levels of anti-human-IgG antibody, nor did it reduce inulin clearance (CsA: 234 +/- 31 microliters/minute/100 gm body weight; controls: 119 +/- 27 microliters/minute/100 gm body weight). Morphologic studies did not reveal any differences between controls and the immunosuppressed rats. CsA failed to reduce proteinuria in the nonimmune mediated model of aminonucleoside nephrosis. The data demonstrate that Cyclosporin A can prevent the induction and more importantly ameliorate already established proteinuria in an autologous model of in situ immune complex glomerulonephritis. This latter finding is important since, in general, most treatment schedules have little, if any effect on established experimental glomerular disease.

Animals↗
PubMed1987

Urinary protein patterns and EPH-gestosis.

In pregnancy a glomerular or mixed glomerular/tubular proteinuria in excess of 0.5 g/day was found in EPH-gestosis or preceding glomerular disease. A pure tubular proteinuria was not found in EPH-gestosis. The severity of the clinical picture was positively correlated with the daily protein loss.

Diagnosis, Differential↗
PubMed1986

Detection of a metalloproteinase in patients with acute and chronic renal failure.

The effect of different dialyzer membrane materials (cuprophan, cellulose hydrate, polyacrylonitrile, polymethylmethacrylate, ethylene-vinyl alcohol copolymer) on the ultrafiltrate proteinase activity was investigated in 26 patients with acute renal failure (ARF) and 40 patients undergoing regular hemodialysis treatment (RDT). Furthermore, the proteinase activity was characterized in vitro using azocasein and phosphorylase kinase as substrates in the absence and presence of different proteinase inhibitors. Proteinase activity of ultrafiltrates obtained from ARF patients was significantly enhanced with the dialyzer KF 101 (ethylene-vinyl alcohol copolymer). The digestion pattern of phosphorylase kinase revealed an identical type of proteinases in ultrafiltrates of ARF and RDT patients. The pH optimum of this proteinase was at alkaline pH. The proteinase activity could be inhibited in the presence of EDTA, whereas serine proteinase inhibitors were ineffective. Furthermore, the inactivated proteinase after Sephadex G-10 chromatography (in order to separate ultrafiltrate electrolytes and trace elements from protein) could be reactivated after the addition of Mg++ and/or Ca++. We conclude that a metalloproteinase can be found in ARF and RDT patients, and that KF 101 is more effectively eliminating the proteinase activity in ARF patients than other dialyzer membranes.

Acute Kidney Injury↗
PubMed1986

Mediator systems in a passive model of in situ immune complex glomerulonephritis. Role for complement, polymorphonuclear granulocytes and monocytes.

The pathogenetic roles of complement, polymorphonuclear granulocytes, and monocytes were studied in a model of in situ immune complex glomerulonephritis employing a cationized antigen. Left kidneys of Wistar rats were perfused with 40 micrograms of cationized human IgG (isoelectric point greater than or equal to 9.5) followed by intravenous injection of rabbit anti-human IgG 1 hour later. This resulted in prominent subepithelial deposit formation in the perfused kidney accompanied by massive proteinuria. Groups examined were: (a) no additional treatment, (b) C3 depleted (cobra venom factor, (c) granulocyte depleted (specific antiserum), (d) monocyte depleted (specific antiserum), and (e) granulocyte depleted and monocyte depleted. The quantity of radiolabeled cationized antigen deposited in the left kidney was not affected by any of the treatment schedules. Proteinuria was abolished in all mediator depleted groups (b to e) for 5 to 7 days, thereafter rising to levels seen in the nondepleted group (a). This late onset of proteinuria is noteworthy since the deposits are then located subepithelially and may be less accessible to circulating mediators. C3 depletion, despite inhibition of proteinuria, did not prevent the intraglomerular accumulation of granulocytes and monocytes thereby suggesting that attraction and activation of these cells may occur independently. Apparently all three mediators are required for full expression of the lesion, a finding not paralleled in other experimental models of glomerulonephritis. The relevance of very low levels of inflammatory cell infiltration for provoking glomerular injury was clearly demonstrated.

Animals↗