Insulin--a growth hormone.

Endocrinology and Diabetes Research Unit, Schneider Children's Medical Center of Israel, WHO Collaborating Center for the Study of Diabetes in Youth, Sackler Faculty of Medicine, Tel Aviv University, Petah Tikva, Israel.
Archives of Physiology and Biochemistry 03/2008; 114(1):11-6. DOI: 10.1080/13813450801928356
Source: PubMed

ABSTRACT Insulin is a peptide hormone with a high degree of homology with the insulin-like growth factor I (IGF-I). Its biological actions are interlaced with those of GH and IGF-I. The objective of this study is to review the growth promoting actions of insulin. The experimental evidence consists of the use of organ cultures of neonatal mice condilar cartilage insulin which stimulates the cartilage cell differentiation and maturation. Injection of insulin to hypohysectomized rats stimulated tibial growth. Clinical evidence is manifold. Babies with diabetes and hypoinsulinemia are short, whereas babies with hyperinsulinism are big. Children with idiopathic short stature have low insulin whereas obese children with hyperinsulinism are tall. Hypo-insulinized children with diabetes slow their growth until the insulin dose is optimized. It remains to be clarified whether insulin exerts its growth promoting actions via its own receptors, via the IGF-I receptors, or via a hybrid (insulin--IGF-I) receptor.

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