Stimulation of follistatin production by epidermal growth factor in cultured rat hepatocytes.
Production of follistatin in cultured rat hepatocytes was studied by measuring follistatin release with a protein-binding assay using [125I]activin A. Follistatin was detected in conditioned medium of cultured hepatocytes. Ligand blotting using [125I]activin revealed that follistatin released into the medium consisted of two different forms with molecular weight of approximately 40 K-Da. Epidermal growth factor (EGF) elicited dose-dependent increases in DNA synthesis and follistatin release. Dose-response relationship for EGF-induced follistatin release correlated well with that for EGF-induced DNA synthesis. In EGF-stimulated cells, a marked increase in DNA synthesis occurred after 48 hrs. Similarly, follistatin release was markedly augmented after 48 hrs. Amount of cell-bound follistatin was not changed by the treatment with EGF. These results indicate that cultured hepatocytes synthesize and release follistatin. The activin-follistatin system operates in cultured rat hepatocytes and may modulate DNA synthesis by altering the action of activin A.
Cell Biology Research Unit, Gunma University, Maebashi, Japan.
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Kanzaki
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Zhang
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Mine
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Kojima
D028341:Activins; D000818:Animals; D002478:Cells, Cultured; D004247:DNA / Q000096:biosynthesis; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D038681:Follistatin; D006023:Glycoproteins / Q000096:biosynthesis* / Q000378:metabolism; D006133:Growth Substances / Q000378:metabolism; D006801:Humans; D007265:Inhibins / Q000378:metabolism; D007700:Kinetics; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins / Q000378:metabolism; D013936:Thymidine / Q000378:metabolism
D038681:Follistatin; D006023:Glycoproteins; D006133:Growth Substances; D011994:Recombinant Proteins; D028341:Activins; D007265:Inhibins; D004815:Epidermal Growth Factor; D004247:DNA; D013936:Thymidine