Impairment of cysteine synthesis from methionine in rats exposed to surgical stress.
The activity of liver cystathionase (EC 4.4.1.1) was decreased after 3 d of stress induced by surgery. The rate of L-cysteine synthesis from L-methionine was significantly higher in isolated hepatocytes from controls than in hepatocytes from rats suffering from surgical stress. The half-life of L-[2(n)-3H]methionine was significantly higher in rats submitted to surgical stress than in controls. Plasma L-methionine:L-cystine ratio was higher in stressed rats than in controls. L-cystine uptake was significantly increased in the surgically-stressed rats when compared with the controls. All these facts are consistent with the hypothesis that the observed inhibition of cystathionase is physiologically important and that L-cysteine might be considered as an essential amino acid in cases of surgical stress.
Viña
J
J
Departamento de Fisiología, Facultad de Medicina, Valencia, Spain.
Gimenez
A
A
Puertes
I R
IR
Gasco
E
E
Viña
J R
JR
D000111:Acetylcysteine / Q000494:pharmacology; D000818:Animals; D001835:Body Weight / Q000502:physiology; D002478:Cells, Cultured; D003542:Cystathionine gamma-Lyase / Q000378:metabolism; D003545:Cysteine / Q000096:biosynthesis*; D004435:Eating / Q000502:physiology; D008099:Liver / Q000166:cytology / Q000378:metabolism*; D008297:Male; D008715:Methionine / Q000378:metabolism* / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013312:Stress, Physiological / Q000150:complications / Q000378:metabolism*; D013514:Surgical Procedures, Operative / Q000009:adverse effects*
D008715:Methionine; D003542:Cystathionine gamma-Lyase; D003545:Cysteine; D000111:Acetylcysteine