Comparison of cytotoxicity of cysteine and homocysteine for renal epithelial cells.

Background: Although the cytotoxic effects of cysteine (Cys) on renal cells have been established, the effects of homocysteine (Hcy), which causes endothelial cell dysfunction, have not been well tested. We compared the direct toxicity of Hcy on renal tubular cells to that of Cys and examined the mechanism of cell toxicity.

Methods: LLC-PK1 cells were incubated with test media containing 500 microM Cys or Hcy in the presence or absence of 100 microM copper.

[A case of sarcoidosis overlapping with rheumatoid arthritis].

We report the case of a 54-year-old woman who presented on May 28, 2001 with sarcoidosis overlapping with rheumatoid arthritis. She had experienced morning stiffness 2 years previously and was diagnosed as having rheumatoid arthritis. She had been treated with bucillamine and loxoprofen for 3 months.

A nitric oxide-generating beta-blocking agent prevents renal injury in the rat remnant kidney model. Comparative study of two beta-blocking drugs, nipradilol and propranolol.

Background: The L-arginine-nitric oxide (NO) pathway plays an important role in the modulation of glomerular disease. We investigated whether beta-blocking agents, with and without an NO-generating function, had renoprotective effects in the 5/6 nephrectomized rats (Nx), an animal model of glomerulosclerosis.

Methods: Nipradilol, a beta-blocker with an ONO(2) group (5, 10 or 15 mg/kg/day) and propranolol, a beta-blocker without this group (50 mg/kg/day) were administered for 12 weeks to Nx together with and without nitro-L-arginine methyl ester (L-NAME).

Association of hyperhomocysteinemia with plasma sulfate and urine sulfate excretion in patients with progressive renal disease.

Background: Plasma total homocysteine (tHcy) level is increased in patients with renal disease, parallel to serum creatinine concentration. In renal failure, the final product of sulfated amino acid metabolism, sulfate, also accumulates as renal function declines. We hypothesized that the elevation in sulfate level could cause hyperhomocysteinemia and tested the relation between tHcy level and both urinary excretion and plasma levels of sulfate.