Effect of starvation of the synthesis rate of albumin in vivo and its relation to the concentrations of amino acids in the peripheral blood, the portal circulation and in the liver cytosolic fraction.
The synthesis rate of albumin was measured in vivo by the 14C-carbonate method in fed control rabbits, in animals after a short-term fast (24-36h), and after starvation for 8 days. The albumin synthesis rate was significantly lower in animals after a short-term fast in comparison to the fed control group. A starvation for a longer period did not further decrease the synthesis rate of albumin. The serum concentrations of essential amino acids from the systemic circulation and from the portal blood after a short-term fast did not differ significantly nor were they higher in comparison to those of fed rabbits. Despite the increased serum levels of the most essential amino acids in the systemic venous blood after long-term  starvation, there were no or little changes in concentrations of amino acids in portal blood and liver cytosolic fraction from fasted animals as compared to those of the fed group. These findings suggest that the reduction of albumin synthesis in fasting state is not primarily due to a reduction in the direct availability of these amino acids for albumin synthesis in the liver.
D000418:Albumins / Q000096:biosynthesis*; D000596:Amino Acids / Q000097:blood / Q000378:metabolism*; D000601:Amino Acids, Essential / Q000097:blood / Q000378:metabolism; D000818:Animals; D001810:Blood Volume; D003600:Cytosol / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008297:Male; D011168:Portal System; D011817:Rabbits; D013217:Starvation / Q000378:metabolism*
D000418:Albumins; D000596:Amino Acids; D000601:Amino Acids, Essential