Horm Metab Res 1994; 26(8): 363-366
DOI: 10.1055/s-2007-1001707
Originals Basic

© Georg Thieme Verlag, Stuttgart · New York

Growth Hormone (GH) Stimulates Insulin-Like Growth Factor-I (IGF-I) and IGF-Binding Protein (IGFBP)-2 Gene Expression in Spleens of Juvenile Rats

Shoshana Yakar1 , H. Domene2 , Rina Meidan1 , F. Cassorla2 , Irit Gilad3 , I. Koch4 , Z. Laron3 , C. T. Roberts1  Jr. , D. LeRoith1 , Rina Eshet3
  • 1Diabetes Branch, National Institute of Diabetes and Digestive and Kidney Diseases
  • 2Developmental Endocrinology Branch, National Institute of Child and Human Development, National Institutes of Health, Bethesda, Maryland, U.S.A.
  • 3Endocrine and Diabetes Research Unit, Children's Medical Center of Israel, Beilinson Campus, Petach Tikva and Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv
  • 4Department of Hormone Research, Weizmann Institute for Science, Rehovot, Israel
Further Information

Publication History

1994

1994

Publication Date:
14 March 2008 (online)

Summary

Growth and development of the spleen involves the growth hormone (GH)/insulin-like growth factor-I (IGF-I) axis. To evaluate the molecular mechanism of these effects we studied the effect of hypophysectomy (Hx) and GH replacement therapy on the expression of IGF-I, the IGF-I receptor and IGF-binding protein-2 (IGFBP-2) in juvenile rats. Hx resulted in a 30% reduction in body weight. GH replacement therapy for seven days partially prevented these effects. IGF-I mRNA levels were reduced 30% by Hx, IGFBP-2 mRNA levels fell 50% whereas IGF-I receptor mRNA levels were unaffected. GH therapy prevented the reduction in IGF-I and IGFBP-2 mRNA levels. These results suggest that the GH effect on splenic growth and development is via local (paracrine) IGF-I expression, in addition to any effect by circulating (endocrine) IGF-I.

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