Tryptophan metabolism in D-galactosamine-induced liver injury.
We have reported that in rats with D-galactosamine-induced liver injury, the serum level of indoleacetic acid (IAA), a metabolite of tryptophan (TRP), increases before the increase in serum transaminase activity. To determine whether this IAA is derived from hepatocytes, isolated hepatocytes were treated with D-galactosamine and loaded with TRP, and the changes in TRP and IAA levels in the culture supernatant of the isolated hepatocytes were measured at various time intervals. As a result, IAA level in the culture supernatant of hepatocytes treated with D-galactosamine and loaded with TRP significantly increased in a time-dependent manner. This indicates that in D-galactosamine-induced liver injury, a metabolic pathway which produces IAA from TRP through tryptamine is present in hepatocytes.
Mizoguchi
Y
Y
Third Department of Internal Medicine, Osaka City University Medical School, Japan.
Kodama
C
C
Sakai
M
M
Sakagami
Y
Y
Kobayashi
K
K
Morisawa
S
S
Yamamoto
S
S
Yamada
J
J
D000818:Animals; D002478:Cells, Cultured; D056486:Chemical and Drug Induced Liver Injury; D005688:Galactosamine; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism; D007210:Indoleacetic Acids / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008107:Liver Diseases / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000378:metabolism; D014363:Tryptamines / Q000378:metabolism; D014364:Tryptophan / Q000378:metabolism*
D007210:Indoleacetic Acids; D014363:Tryptamines; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D005688:Galactosamine; D014364:Tryptophan