Androgen metabolism in cultured rat renal inner medullary collecting duct (IMCD) cells.

Although the stimulations of renal hypertrophy and renal erythropoietin production have been well-known androgen effects in the kidney, recent investigative progresses are further providing good evidences for androgen-regulated gene productions of key enzymes or local hormone substrates important to renal cell metabolisms and tubular functions in mouse or rat proximal tubules, respectively. It has been also reported that testosterone restores vasopressin receptors in medullary collecting ducts of the ageing rat and improves a urinary concentrating ability. Therefore in the present study we examined a metabolic pathway of androgens in cultured rat renal IMCD cells, which finally determine a urinary composition and volume. IMCD cells cultured from kidneys of male Wistar rats weighing about 200 g were incubated with serum-free culture media containing 4 nM [3H] testosterone or [3H] androstenedione for 2-48 h. Radioactive compounds in incubation media were then separated by reverse-phase high-pressure liquid chromatography (HPLC) and identified mainly on the basis of comparison of retention times of standard materials on HPLC. The main metabolites identified in testosterone or androstenedione incubation experiment were 5 alpha-dihydrotestosterone or 5 alpha-androstanedione, respectively. 5 alpha-Reductase inhibitor, MK 906, effectively inhibited the formations of these Ring A reduced metabolites. These results may suggest that rat renal IMCD cells possess 5 alpha-reductase activity, thereby converting androgens into their biologically active forms in vivo.

[A hemodialysis patient with HTLV-1-associated myelopathy (HAM)].

We report here a case of maintenance hemodialysis with HTLV-1 associated myelopathy (HAM). A 53-year-old female hemodialysis patient was admitted to Teikyo University Ichihara hospital because of paralytic ileus. She had a history of blood transfusion and had been under dialysis treatment for 8 years. She had experienced gait disturbance and sensory disturbance in her lower extremities for 8 years. Neurological examination revealed myelopathy and neuropathy. Laboratory data revealed that serum anti-HTLV-1-antibody was over 1260 x (PA) and liquor HTLV-1-antibody was over 160 x (PA). Her liquor revealed a cell count of 4/3 cmm, protein 22 mg/dl, glucose 45 mg/dl, chloride 125 mEq/l and no atypical cells. To the best of our knowledge this is a rare case in Japan. Our findings suggest that HAM should be taken into consideration when we diagnose a maintenance hemodialysis patient showing neuropathy and myelopathy.

[An adult case of hemolytic uremic syndrome (HUS) after pathogenic Escherichia coli (E. coli) infection].

In recent years, it has been revealed that verocytotoxin-producing E. coli (VTEC) infection is one of the leading causes of HUS and the molecular aspects of its pathophysiology have also been studied extensively. We report a case of a 56-year-old man who developed HUS after E. coli (O 26 strain) infection with diarrhea. The characteristic laboratory findings in this case included hypergammaglobulinemia, hypocomplementemia and a high level of immune complex in addition to the common findings of HUS. The light microscopic findings of the first renal biopsy performed before treatment revealed extensive interstitial changes with remarkable mononuclear cell infiltrations as well as mild mesangial proliferation with crescent formation. Subendothelial electron-dense deposits within the glomerular capillary walls and mesangial area were also detected by electron microscopic examination. The diagnostic possibilities of infectious endocarditis and collagen diseases, such as Sjögren syndrome, were reasonably ruled out by the appropriate examinations. After 2-month prednisolone therapy, proteinuria and deteriorated renal functions as well as the abnormal immunological parameters described above were remarkably improved. The second renal biopsy after treatments showed clearly diminished subendothelial deposits and interstitial mononuclear cell infiltrations. This case report might provide information on the unique features of renal interstitial damage and immunological abnormalities in VTEC-induced adult HUS.