THE GROWTH-HORMONE (GH)-INDEPENDENT GROWTH OF THE OBESE ZUCKER RAT IS NOT DUE TO INCREASED LEVELS OF GH RECEPTOR MESSENGER-RNA IN THE LIVER

MOLECULAR AND CELLULAR ENDOCRINOLOGY

卷:113

Article

DUBUIS, JM ; DEAL, CL ; VANVLIET, G

关键词: OBESITY (ZUCKER RAT);    GROWTH;    GROWTH HORMONE;    GROWTH HORMONE RECEPTOR;    INSULIN-LIKE GROWTH FACTOR-I;    BINDING PROTEIN;   

DOI  :  10.1016/0303-7207(95)03631-G

来源: Elsevier

【 摘 要 】

Obese Zucker rats maintain normal rates of linear growth and circulating concentrations of insulin-like growth factor-I (IGF-I) and of IGF-binding protein-3 (IGFBP-3) in spite of low GH secretion. The mechanisms underlying this GH-independent growth in obesity are unknown. To assess whether the liver expression of the GH receptor (GHR) messenger RNA (mRNA) is increased and/or if the liver expression of IGFBP-3 mRNA is maintained in the obese, Zucker rats of both genders and phenotypes (four groups, n = 6/group) were studied at 12 weeks of age. By Northern analysis, mRNA levels for GHR and GHBP were not increased in obese rats compared to their sex-matched lean littermates; the expression of these two transcripts was sexually dimorphic and the changes in GHBP mRNA/GHR mRNA ratios associated with obesity were sex-specific. In both genders, IGFBP-1 and IGFBP-3 mRNAs were decreased in the obese. We conclude that the GH-independent growth of obese Zucker rats is not due to increased GHR mRNA or to maintained IGFBP-3 mRNA levels in the liver.

【 授权许可】

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