Iodine Concentration in Rabbit Kidneys After Diodrast Injection

Publisher Website
Google Scholar
Abstract
Varying amts. (0.1-16 ml./kg. body wt.) of 35% Diodrast soln. were given rabbits in single intraven. injns. Animals were sacrificed after an interval of 3-60 min. and their kidneys, plasma, liver and urine analyzed for Diodrast I. In animals killed after a constant interval (10 min.) the I concn. in the plasma and liver was proportional throughout to the amt. injd. Kidney iodine increased, too, with increasing injns., but when less than 1 ml./kg. body wt. was injd. the concn. rose much more rapidly with increasing injns. than if more than 1 ml./kg. was injd. When carinamide was given before Diodrast injn. the I concn. in the kidneys was lower than in the controls, and less Diodrast was excreted with the urine; but when carinamide was given 10 min. after Diodrast, the kidney I concn. was higher than in the controls, in spite of a lower urinary excretion. The conclusion was drawn that the excreting cells in the kidney tubules can accumulate Diodrast on its way out. This accumulation occurs when the transferring cells receive more Diodrast than they are able to excrete. Their capacity to accumulate Diodrast was limited. If p-amino-hippurate was given shortly before Diodrast it occupied a part of this capacity and less Diodrast could be accumulated. Tubular nephritis achieved by means of uranium poisoning diminished the accumulation capacity. The renal tubular excretion seems to consist of 2 steps: the entrance of the substance to be excreted into the transferring cells, and the excretion from the cells into the urine. It is the 2d step that limits the excretory capacity.