[A new test selectively characterizing specific kidney function]

The effect of total x-ray irradiation on distribution and elimination of 51Cr cations was studied on 60 white noninbred rat males. The radionuclide was introduced intragastrically and intravenously 0.5-1 hour after the irradiation. Chromatographic and spectrophotometric investigation of the marker was performed in the serum and urine. It was established that Cr3+ is absorbed from the gastrointestinal tract by means of facilitated diffusion with glutamine as the carrier. Its urinary excretion reflects proportionally the degree of developing acidosis and selectively the process of chromium glutaminate deamidation in the kidneys. It is suggested to determine urinary Cr3+ elimination as a new test instead of using ammonia which is produced both by deamidation and deamination.