Andrew J. Adler

Use of Extracorporeal Ascites Dialysis in Combined Hepatic and Renal Failure

Dialytic therapy was performed in 2 patients with combined hepatic and renal failure by dialyzing ascitic fluid extracorporeally through an artificial kidney and returning it to the peritoneal cavity.

The effect of aluminum on the vanadium-mediated oxidation of NADH.

Aluminum catalyzes the oxidation of NADH by vanadate both in the presence and absence of a reducing sugar. The effect of aluminum is concentration dependent and inhibitable with superoxide dismutase but not catalase. The fructose-6-phosphate-free reaction is characterized by an initial lag phase which can be eliminated by preincubating aluminum with NADH, but is not altered by preincubating aluminum with vanadate, suggesting that the effect of aluminum is not directly on vanadate. Aluminum also catalyzes vanadyl-mediated oxidation of NADH, and this effect is similarly inhibitable by superoxide dismutase as well as catalase. It is suggested that aluminum catalyzes the oxidation of NADH by vanadium though enhancing the production of superoxide radicals and that this effect may account in part of the biological toxicity associated with aluminum, particularly when associated with the accumulation of other trace elements such as vanadium.

Uptake and Distribution of 45Ca in the Brain of Chronically Uremic Rats

The exchange of calcium between serum, cerebrum and cerebral mitochondria was studied in chronically uremic rats. Chemical and radiocalcium assays were performed at periods from 1 to 48 h following intracardiac injection of 45Ca. The disappearance of 45Ca from the serum of uremic rats was identical to that observed in normals. Maximal uptake and equilibration with serum by both cerebrum and cerebral mitochondria were assessed in uremic rats by means of relative specific activities (RSAs) and found not to differ significantly from normal. Peak levels occurred at 6 h for cerebrum and between 4 and 6 h for mitochondria. These results indicate that in the rat, calcium uptake by the brain over a period of 48 h is not altered by chronic renal failure. Moreover, the findings in brain mitochondria suggest that the intracellular calcium burden may not be increased by uremia.