EFFECT OF EPIDERMAL GROWTH-FACTOR ON INSULIN-LIKE GROWTH FACTOR-I (IGF-I) AND IGF-BINDING PROTEIN-SYNTHESIS BY ADULT-RAT HEPATOCYTES

MOLECULAR AND CELLULAR ENDOCRINOLOGY

卷:84

Article

BARRECA, A ; VOCI, A ; MINUTO, F ; DEMARCHIS, M ; CECCHELLI, E ; FUGASSA, E ; GIORDANO, G ; GALLO, G

关键词: INSULIN-LIKE GROWTH FACTOR-I;    INSULIN-LIKE GROWTH FACTOR BINDING PROTEIN;    EPIDERMAL GROWTH FACTOR;    HEPATOCYTE;    BIOSYNTHESIS;    LIVER REGENERATION;   

DOI  :  10.1016/0303-7207(92)90078-K

来源: Elsevier

【 摘 要 】

Growth hormone has been established as a primary regulator of IGF-I gene expression in adults, not only in liver but also in many extrahepatic tissues. We considered the possibility that IGF-I production by adult rat liver could also be stimulated by epidermal growth factor (EGF), a peptide known to be involved in liver regeneration. Chromatographic analysis performed after acid treatment of conditioned media revealed the presence of both immunoreactive (IR) IGF-I and IGF binding protein (IGFBP). Both IR IGF-I and IGFBP were present in the conditioned medium of adult rat hepatocytes in basal conditions. The stimulation of IGF-I and IGFBP secretion by EGF appears to be dose-dependent with a significant increment already evident at 5 nM. That EGF stimulates secretion is supported by the finding that IGF-I and IGFBP-1 mRNA levels are increased after EGF supplementation. We conclude that adult rat hepatocytes spontaneously produce IGF-I and IGFBP, and that EGF is able to increase their synthesis and secretion. This non-growth hormone-dependent regulation of IGF-I and IGFBP-1 production by adult rat hepatocytes in culture indicates an important autocrine/paracrine role for IGF-I, particularly during liver regeneration after extensive organ mass loss.

【 授权许可】

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