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Growth promotion by homocysteic acid
Science (New York, N.Y.)
|April 23, 1976
Summary
Homocysteic acid, a sulfur amino acid, significantly promotes growth in rats by increasing tibia and tail growth. This compound also elevates serum somatomedin activity, linking sulfur amino acid metabolism to growth hormone action.
Area of Science:
- Biochemistry
- Endocrinology
- Physiology
Background:
- Sulfur amino acid metabolism is crucial for various physiological processes.
- Homocysteic acid's role in growth regulation is not fully understood.
- Growth hormone (GH) and somatomedins are key regulators of skeletal growth.
Purpose of the Study:
- To investigate the growth-promoting effects of homocysteic acid in a hypophysectomized rat model.
- To determine if homocysteic acid influences serum somatomedin activity.
- To explore the connection between sulfur amino acid metabolism and growth hormone physiology.
Main Methods:
- Hypophysectomized rats were used for tibia and tail growth assays.
- Growth was quantified by measuring epiphyseal cartilage thickness and tail length.
- Serum somatomedin activity was assessed using a porcine cartilage disk assay.
Main Results:
- Homocysteic acid administration significantly increased tibia and tail growth in hypophysectomized rats.
- Low doses of homocysteic acid (1 microgram/day for tibia, 2.5 mg/kg/day for tail) were effective.
- Serum somatomedin activity was elevated following homocysteic acid treatment.
Conclusions:
- Homocysteic acid exhibits growth-promoting properties, potentially mediated by somatomedin.
- These findings establish a link between sulfur amino acid metabolism and growth hormone-regulated growth.
- The study has implications for understanding homocystinuria, arteriosclerosis, and cellular growth control.
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