thromboxane-b2 and Nephrosis--Lipoid

Topics: 6-Ketoprostaglandin F1 alpha; Adult; Female; Humans; Male; Middle Aged; Nephrosis, Lipoid; Thromboxane B2

Topics: Adult; Blood Platelets; Case-Control Studies; Child; Cyclic AMP; Glomerulosclerosis, Focal Segmental; Humans; Nephrosis, Lipoid; Platelet Aggregation; Thromboxane B2

Mizoribine (MZR), a purine nucleoside antibiotic, is an effective immunosuppressive agent that prevents rejection reactions after kidney transplantation in humans. The present study was performed to examine the effect of MZR on nephrosis produced in rats given puromycin aminonucleoside (PAN). Urinary protein excretion in rats injected with PAN and MZR (PAN + MZR rats) was shown to be reduced significantly in comparison with rats given only PAN (PAN rats). Although mild hypoproteinemia persisted during the experimental period in PAN + MZR rats, no loss of body weight or state of malnutrition was observed. The reduction of serum IgG and C3 was reversed by administration of MZR. Polyethyleinamine (PEI) staining of renal sections showed increased numbers of anionic sites in PAN + MZR rats in comparison with PAN rats, suggesting that MZR improved the permselectivity of the glomerular basement membrane (GBM). Moreover, the production of thromboxane B2 (TxB2) was significantly inhibited in PAN + MZR rats compared with PAN rats. No serious adverse effects of MZR were observed after a large dose of the agent. It is possible that restoration of the charge barrier of the GBM damaged by PAN, or reduction of TxB2 production by the glomeruli may underlie the reduction of protein excretion induced by administration of MZR.

Topics: Animals; Antibiotics, Antineoplastic; Immunosuppressive Agents; Male; Nephrosis; Nephrosis, Lipoid; Proteinuria; Puromycin Aminonucleoside; Rats; Rats, Wistar; Ribonucleosides; Thromboxane B2

The administration of a single-injection of Adriamycin (ADR) to rats results in marked proteinuria and glomerular morphological changes that are similar to minimal change disease in humans. We have hypothesized that Adriamycin, by itself or through the release of some mediators from resident glomerular cells, could provoke a damage to epithelial glomerular cells. Sprague-Dawley rats received a single injection of Adriamycin, 7.5 mg/kg bw, allocated randomly in several groups and treated throughout 2 weeks of follow-up. All control nontreated animals developed important nephrotic syndrome and degenerative lesions of epithelial glomerular cells. Isolated glomeruli from animals injected with adriamycin 14 days before synthesized thromboxane (TxB2) and platelet activating factor (PAF) in amounts above the rates of control glomeruli. Animals treated with three structurally different PAF receptor antagonists did not present proteinuria or only to a very low extent (p less than 0.0005). In these rats no alterations in epithelial cells were noted. Furthermore, no significant changes in the TxB2 production were noted in rats treated with BN 52021, a PAF receptor antagonist. Leukotrienes also seem to participate since treatment with a 5-lipoxygenase inhibitor partially corrected proteinuria. Moreover, glomeruli from animals with nephrosis and treated with this compound presented only a discrete reduction in the PAF synthesis. On the whole, these data suggest a key role for PAF in the pathogenesis of adriamycin nephropathy. Other lipid meditors, released in cascade simultaneously or thereafter, could perpetuate the renal damage.

Topics: Animals; Dinoprostone; Doxorubicin; Kidney Glomerulus; Lipoxygenase Inhibitors; Male; Nephrosis, Lipoid; Platelet Activating Factor; Platelet Membrane Glycoproteins; Proteinuria; Random Allocation; Rats; Rats, Inbred Strains; Receptors, Cell Surface; Receptors, G-Protein-Coupled; Thromboxane B2

An evaluation was made of the possible relation between renal thromboxane (Tx)A2 synthesis (measured as urinary excretion of TxB2) and the loss of glomerular permeability to proteins, in 5 children with seven episodes of minimal change nephrotic syndrome. Urinary TxB2 excretion was significantly higher in children with minimal change nephrotic syndrome than in 14 healthy controls, and reached its maximum at the time of peak proteinuria. During remission of nephrotic syndrome urinary excretion of TxB2 was still significantly higher than in healthy controls. A significant positive correlation between urinary excretion of TxB2 and proteinuria was observed in 3 patients. The results suggest that renal TxA2 could be regarded as one of the possible mediators of the altered glomerular permeability to proteins in minimal change nephrotic syndrome.

Topics: Child; Female; Humans; Kidney; Male; Nephrosis, Lipoid; Proteinuria; Thromboxane A2; Thromboxane B2

To determine if a selective thromboxane (TX)A2 synthetase inhibitor is clinically effective for the treatment of nephrotic syndrome, 11 patients with nephrotic syndrome were treated only with OKY-046, (E)-3-4-(1-imidazolylmethyl)phenyl-2-propenoic acid hydrochloride monohydrate, for at least 8 weeks. Urinary excretion of protein, TXB2, 2,3-dinor-TXB2, and beta-N-acetyl-D-glucosaminidase decreased with OKY-046. Creatinine clearance value, and urinary excretion of 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha), however, did not show any significant change, while serum albumin level increased. Two patients with minimal change nephrotic syndrome showed complete remission only with OKY-046. These results demonstrate that the selective TXA2 synthetase inhibitor is an effective drug for the treatment of chronic glomerulonephritis accompanied by nephrotic syndrome.

Topics: 6-Ketoprostaglandin F1 alpha; Acrylates; Adolescent; Adult; Aged; Female; Glomerulonephritis; Humans; Male; Methacrylates; Middle Aged; Nephrosis, Lipoid; Nephrotic Syndrome; Proteinuria; Thromboxane B2; Thromboxane-A Synthase

Topics: Adolescent; Adult; Chronic Disease; Female; Glomerulonephritis; Glomerulosclerosis, Focal Segmental; Humans; Male; Middle Aged; Nephrosis, Lipoid; Radioimmunoassay; Thromboxane B2; Thromboxanes