Somatotropin is a 191 amino acid polypeptide hormone. Somatotropin is made up of four helices containing 21-30 amino acids each. The structure of somatotropin is "characterized by an anti-parallel up-up-down-down arrangement of the helices. It is considered a "compact and stable molecule." Somatotropin is synthesized and secreted by somatrophs of the anterior pituitary gland, which is situated in the base of the brain. There are many other properties of somatotropin that are listed below.
| Compound Name |
Somatotropin (human growth hormone)
|
Compound Formula |
see sequence below
|
Molar Mass |
21864 g
|
Where is it found |
in humans
|
Natural Abundance |
produced by the body (about 10 mg till 30yrs old)
|
How is it obtained |
originally extracted from humans but is now made in laboratories
|
Type of Bonding |
Covalent
| |
The melting point, boiling point, and density of somatotropin are seemingly insignificant properties and therefore are not commonly discussed in books and other reliable sources. The percent composition by mass and percent composition by number are not commonly calculated for somatotropin because it is a protein and such information appears not to be significant in the research of the functions and properties of the compound.
Somatotropin reacts with many different substances. Two of the primary substances that react with somatotropin are growth hormone releasing hormone and somatostatin. Growth hormone releasing hormone, also known as GHRH, and somatostatin are both hormones located in the hypothalamus of the brain. Growth hormone releasing hormone is a hormone that causes the secretion of somatotropin. It has been clinically found that when normal humans are injected with GHRH, somatotropin is released within minutes of the injection. The amount of growth hormone released reaches an apex thirty minutes after the injections and can maintain this high level of growth hormone secretion for 1 to 2 hours.
The discovery of Somatotropin occurred somewhere in the early 1900's. The majority of scientists claim that it was discovered in the 1930's. This discovery cam about after it was found that when rats were injected with "a crude rat pituitary extract" in the growing phase, the rats went through an increased growing rate. About two decades later, in the 1950's, it was found that human dwarfism resulted from insufficient production of Somatotropin. In the 1980's it was discovered that growth hormone could be made in the lab. This discovery led to the decrease in prices for somatotropin treatment as well as increased amount of treatment available to people with somatotropin deficiency.
The order of these 191 amino acids is listed below using the one letter abbreviation of the amino acid names. The sequence is listed below: