Human Growth Hormone (HGH) is a hormone produced by the pituitary gland (pituitary is one of the endocrine glands). The pituitary gland is located in the center of the brain. HGH is also a very complex hormone. It is made up of 191 amino acids - making it fairly large for a hormone. In fact, it is the largest protein created by the Pituitary gland.
HGH secretion reaches its peak in the body during adolescence. HGH helps stimulate our body to grow. But, HGH secretion does not stop after adolescence. Our body continue to produce HGH usually in short bursts during deep sleep.
Human Growth Hormone is known to be critical for tissue repair, muscle growth, healing, brain function, physical and mental health, bone strength, energy and metabolism. In short, it is very important to just about every aspect of our life.
Recombinant Growth Hormone is GH that is synthesized in the lab. It is a biosynthetic hormone that is identical to human growth hormone in structure. Creating an exact replicate of HGH was not an easy task.
First scientist needed to isolate HGH. Once they achieved this step they could study the DNA make-up of the protein. Scientist quickly realized making recombinant GH would be no easy task since they had to accurately reproduce a 191 amino acid hormone.
Primary driving force behind this research was not to help mankind, but rather financial reward. Pharmaceutical companies knew that there was big money to be made if they could create HGH in a test tube. Scientist from the major drug companies raced to produce the 191 amino acid hormone in a test tube. While Genentech first claimed victory in 1985, it was a short lived success. The recombinant GH they made was a 190 amino acid match - they were one amino acid off from HGH. This left the door open for Eli Lilly, who in 1986 created a 191 amino acid hormone that was an identical match to the HGH produced by the pituitary gland. The drug is called Humatrope and is the most widely used recombinant growth hormone today.
IGF-1 stands for Insulin-like Growth Factor 1. IGF-1 is also known as Somatomedin-C. As important as HGH is, it does not last long in our bloodstream. In just a few short minutes our liver absorbs HGH and converts it into growth factors. IGF-1 is the most important growth factor that is produced. So, IGF-1 is a hormone just like HGH, but it is easier to measure in the body because it stays in our bloodstream longer than HGH. You can think of HGH as the hormone that gets the ball rolling, but IGF-1 does most of the work.