Restricted Zn2+ availability affects the antizyme-dependent ornithine decarboxylase degradation pathway in isolated primary cultured rat hepatocytes.
We previously reported that lack of Zn2+ decreased ornithine decarboxylase (ODC) activity without any change in ODC messenger RNA levels and the half-life of ODC activity being about 2-fold more rapid in primary cultured adult rat hepatocytes, suggesting that lack of Zn2+ decreased ODC activity mainly by degrading the enzyme. The present investigations showed that the chelator, diethylenetriamine penta-acetic acid (DTPA), increased the ratio of ODC-antizyme complex to total ODC (about 2-fold) and caused a decrease in antizyme inhibitor, a protein inhibitor of ODC antizyme (about 50%). These results indicate that a restricted Zn2+ availability affects the antizyme-dependent ODC degradation pathway and consequently decreases ODC activity in primary cultured rat hepatocytes.
Nakatani
T
T
Department of Food and Nutrition, Faculty of Human Life Science, Osaka City University, Japan.
Kennedy
D O
DO
Murakami
Y
Y
Yano
Y
Y
Otani
S
S
Matsui-Yuasa
I
I
D000818:Animals; D015153:Blotting, Western; D002478:Cells, Cultured; D002614:Chelating Agents / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004815:Epidermal Growth Factor / Q000494:pharmacology; D007328:Insulin / Q000494:pharmacology; D008099:Liver / Q000201:enzymology*; D009955:Ornithine Decarboxylase / Q000235:genetics / Q000378:metabolism*; D004369:Pentetic Acid / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D015032:Zinc / Q000008:administration & dosage* / Q000494:pharmacology
D002614:Chelating Agents; D004791:Enzyme Inhibitors; D007328:Insulin; D012333:RNA, Messenger; D004815:Epidermal Growth Factor; D004369:Pentetic Acid; D009955:Ornithine Decarboxylase; D015032:Zinc