Metabolism in the hypothermically perfused dog kidney. Incorporation rate of leucine and threonine into proteins.
The incorporation of [14C]leucine and [14C]threonine into kidney cortex proteins was studied during 6 days' hypothermic perfusion of dog kidneys at 8-10 degrees C and during in vitro incubation of dog kidney cortex slices at 37 degrees C. Leucine carbon was incorporated into proteins at a higher rate than threonine carbon both during in vitro incubation of kidney cortex slices and during hypothermic kidney perfusion. The incorporation of leucine and threonine during hypothermic perfusion was linear for 6 days but 50-100 times lower than the incorporation of leucine and threonine in kidney cortex slices at 37 degrees C. During hypothermic perfusion there was a decrease in specific activity of leucine and threonine in the perfusate corresponding to a degradation of proteins which was greater than protein synthesis as calculated from the incorporation of label into proteins. Leucine carbon was recovered in CO2 during hypothermic perfusion and in vitro incubation of kidney cortex slices at 37 degrees C. The incorporation of threonine carbon into CO2 was about 10% of the corresponding value for leucine both during hypothermic kidney perfusion and during in vitro incubation of kidney cortex slices at 37 degrees C. It is concluded that there is a turnover of kidney proteins during hypothermic perfusion with a perfusate containing amino acids.
D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D004285:Dogs; D007036:Hypothermia, Induced; D007668:Kidney / Q000378:metabolism*; D007672:Kidney Cortex / Q000378:metabolism; D007930:Leucine / Q000378:metabolism*; D009926:Organ Preservation; D010477:Perfusion; D014176:Protein Biosynthesis; D011506:Proteins / Q000378:metabolism*; D013912:Threonine / Q000378:metabolism*
D000596:Amino Acids; D011506:Proteins; D013912:Threonine; D007930:Leucine