|
KMID : 0438219730100010351
|
|
Korea University Medical Journal
1973 Volume.10 No. 1 p.351 ~ p.362
|
|
|
Effect of uranium salt on distribution of electrolytes, urea and water in kidney of rabbit
|
|
|
|
|
Abstract
|
|
|
The pathologic physiology of oliguria in acute renal failure remains obscure inspite of extensive studies.
The three mechanisms that have been postulated are : a severe reduction in renal blood flow and glomerular filtration rate, obstruction of the tubules by casts or edema, and excessive back diffusion of the filtrate through a damaged tubular epithelium.
Few studies have been published in which these various possibilities were examined by direct observation of the kidney in vivo in animals with experimental acute renal failure. A study reported that, in the anuric stage of cyanide or mercury poisoning in frogs, flow of fluid from the glomerulus into the beginning of the proximal tubule was normal or even increased. The failure of any urine to appear in the ureter was attributed to gross leakage of tubular fluid from distal segments of the proximal tubule.
Some other researchers studying acute renal failure due to mercury poisoning in rats found glomerular filtration rate per nephron to be significantly reduced. They concluded that anuria resulted from intrarenal vasoconstriction and a subsequent fall in filtration rate. However, still other researchers have investigated the rate of leakage of tubular fluid in anuria caused by mercury poisoning. The findings supported the view that the permeability of the tubule is markedly increased and non-selective during the anuric stage of mercury poisoning. They concluded, therefore, that the mechanism of anuria in these animals was excessive back diffusion of the glomerular filtrate through abnormally permeable tubules.
The present study was made to clarify this problem with particular interest in the possible existence of increased permerbility.
On experiments 80 rabbits weighing 1.5-2.5kg. -10 of them were normal control group, 23 were uranium induced group, 23 were uranium induced group loaded with tap water 50ml per kg prior to experiment, 24 were uranium induced group without water prior to experiment were studied.
Inulin and PAH clearance, sodium, potassium, urea, osmolality in serum and urine were measured. The kidney slices were made for analysis of sodium, potassium, urea and water.
The results were as follows:
1) The PAH and inulin clearance were markedly reduced in uranium induced rabbits than the control ones.
2) The water, sodium, potassium and urea excretion were much diminished in uranium induced rabbits than the control ones.
3) The urine osmolar to serum osmolar ratio approached to near 1.0 in uranium induced rabbits.
4) The free water clearance was obtained in uranium induced rabbits, while free water reabsorption occured in the control ones.
5) The sodium content was lower in inner medulla of uranium induced rabbits than the control ones.
6) The urea content was higher in cortex and outer medulla of uranium induced rabbits than the control ones. However, urea content was lower in inner medulla of uranium induced rabbits than the control ones.
7) The water content was higher in inner medulla of uranium induced rabbits than the control ones.
Therefore, it was concluded that non-selective solute resorption was enhanced by increased permeability of proximal tubule of uranium induced rabbits.
|
|
|
KEYWORD
|
|
|
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|
|
|