Define Growth Hormone (GH)
It is a protein containing 19lamino acids in a single chain. It is secreted by somatotrophs throughout life even though growth stops at adolescence. The main functions of GH are highlighted herewith. The growth hormone:
- Promotes development and enlargement of all tissues during the growing phase of life,
- Helps the bones to enlarge and lengthen and the skin thickens by the effect of growth hormone,
- Increases transport of amino acids through cell membrane and protein synthesis. It promotes positive nitrogen balance and is a protein anabolic hormone, and
- Increases blood glucose level by promoting hepatic output of glucose.
After adolescence, growth hormone secretion decreases. The growth of long bones stop by this time, short bones like lower jaw and nose continue to grow. Hence, before adolescence, growth of body depends on the proper action of growth hormone. Height of an individual depends on the proper action of this hormone. Have you ever thought what would be the consequences of deficiency (hyposecretion) or on the other hand, an increased secretion (hypersecretion) of growth hormone during childhood and at adult stage? The discussion below describes both of these conditions.