Increased liver alanine in the tumour-bearing host. Altered levels of some enzymes involved in alanine metabolism.
A 2-fold increase in hepatic alanine concentration was observed in rats bearing a Walker 256 carcinoma growing sub-cutaneously. Decreases were observed in the activities of both cytosolic and mitochondrial isozyme forms of L-alanine-2-oxoglutarate aminotransferase. Activities of two enzymes involved in a secondary pathway of haem synthesis involving alanine, L-alanine-4,5-dioxovalerate aminotransferase and the NADP-requiring isozyme form of 4-oxo-5-hydroxyvalerate dehydrogenase were also reduced but there was no change in liver porphyrin concentration. L-alanine-glyoxalate aminotransferase activity was unaffected. The results are discussed in relation to the utilisation of alanine as a gluconeogenic substrate in the tumor-bearing host.
Department of Biochemistry and Microbiology, University of St. Andrews, Fife, Scotland, U.K.
G A
GA
Goodlad
E
E
Jaffray
K
K
Loudon
C M
CM
Clark
D000409:Alanine / Q000378:metabolism*; D000410:Alanine Transaminase / Q000378:metabolism*; D000818:Animals; D002279:Carcinoma 256, Walker / Q000201:enzymology / Q000378:metabolism*; D003600:Cytosol / Q000201:enzymology; D005260:Female; D007527:Isoenzymes / Q000378:metabolism; D008099:Liver / Q000201:enzymology / Q000378:metabolism*; D008930:Mitochondria, Liver / Q000201:enzymology; D051381:Rats; D011919:Rats, Inbred Strains; D000637:Transaminases / Q000378:metabolism
D007527:Isoenzymes; D000637:Transaminases; D000410:Alanine Transaminase; C019687:aminolevulinate aminotransferase; C019635:Alanine-glyoxylate transaminase; D000409:Alanine