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The Somatomedin Hypothesis of Growth Hormone Action

Raymond L. Hintz

10.1002/cphy.cp070515

Source: Supplement 24: Handbook of Physiology, The Endocrine System, Hormonal Control of Growth

Originally published: 1999

Published online: January 2011

Full Article on Wiley Online Library



Abstract

The sections in this article are:

1 Early Studies on the Mechanism of Growth Hormone Action
1.1 The Sulfation Factor Hypothesis
2 Characterization of Somatomedin Biological Activity in Serum
2.1 Stimulation of Differentiated Cell Functions
2.2 Increases in DNA, RNA, and Protein Synthesis
2.3 Synthesis and Control
2.4 Mechanisms of Action
2.5 Assays and Serum Levels of Somatomedin
3 Purification of Somatomedin from Serum
3.1 Biochemical Characterization
3.2 The Isolation and Sequencing of Nonsuppressible Insulin‐Like Activity‐S Peptides and the Insulin‐Like Growth Factor Terminology
3.3 Relationship to Nonsuppressible Insulin‐Like Activity‐S and Multiplicating Stimulating Activity
4 Characterization of the Specific Somatomedin Peptides
4.1 Development of Specific Assays
4.2 Pathophysiology of Serum Levels
4.3 Somatomedin Receptor Sites
4.4 Somatomedin Binding Proteins
4.5 Metabolism and Feedback on Growth Hormone Secretion
4.6 Lessons from the RNA and DNA Structures of the Insulin‐like Growth Factors
4.7 Paracrine Actions
4.8 The Dual Effector Hypothesis of Growth Hormone Action
5 Evidence that the Somatomedins are the Major Effectors of the Growth Actions of Growth Hormone
5.1 Indirect Evidence
5.2 Direct Evidence
6 Epilogue
Figure 1. Figure 1.

The finding that the decreased incorporation of 35SO4 into hypophysectomized rat costal cartilage could be corrected by the in vivo administration of growth hormone.

From Chochinov and Daughaday 33
Figure 2. Figure 2.

The initial observation by Salmon and Daughaday 212 that 3SSO4 uptake into hypophysectomized rat costal cartilage could not be increased by the in vitro addition of growth hormone to the incubation medium, but could be stimulated by the addition of serum.

From Chochinov and Daughaday 33
Figure 3. Figure 3.

Schematic representation of the direct and indirect actions of growth hormone.

From Van Wyk et al. 266


Figure 1.

The finding that the decreased incorporation of 35SO4 into hypophysectomized rat costal cartilage could be corrected by the in vivo administration of growth hormone.

From Chochinov and Daughaday 33


Figure 2.

The initial observation by Salmon and Daughaday 212 that 3SSO4 uptake into hypophysectomized rat costal cartilage could not be increased by the in vitro addition of growth hormone to the incubation medium, but could be stimulated by the addition of serum.

From Chochinov and Daughaday 33


Figure 3.

Schematic representation of the direct and indirect actions of growth hormone.

From Van Wyk et al. 266
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Article Title: The Somatomedin Hypothesis of Growth Hormone Action
 

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Raymond L. Hintz. The Somatomedin Hypothesis of Growth Hormone Action. Compr Physiol 2011, Supplement 24: Handbook of Physiology, The Endocrine System, Hormonal Control of Growth: 481-499. First published in print 1999. doi: 10.1002/cphy.cp070515