Anatomy
Fact-checked

At WiseGEEK, we're committed to delivering accurate, trustworthy information. Our expert-authored content is rigorously fact-checked and sourced from credible authorities. Discover how we uphold the highest standards in providing you with reliable knowledge.

Learn more...

What Is GHRH?

Kathy Dowling
Kathy Dowling

Growth-hormone-releasing-hormone (GHRH) is a peptide hormone that is released from the arcuate nucleus located in the hypothalamus. The release of GHRH activates the discharge of growth hormones into the bloodstream, which act to stimulate growth in the body, particularly in long bones such as those found in the arms and legs. Secretion of growth hormone or somatotrophin is inhibited or repressed by a growth-hormone-inhibiting hormone, also called somatostatin.

The hypothalamus is located at the base of brain below the thalamus and is involved in many different functions. It acts to regulate temperature and is involved in metabolism, reproduction, and aggression. Another function includes controlling hormone release in the endocrine system. The endocrine system is made up of glands that secrete hormones into the bloodstream, enabling those hormones to be dispersed throughout the body. Part of the endocrine system is the pituitary gland, which is connected to and controlled by the hypothalamus.

GHRH is released from the hypothalamus.
GHRH is released from the hypothalamus.

Hormones are similar to neurotransmitters or neuromodulators because they produce responses by stimulating receptors located on or inside nerve cells. The difference is that they work over longer distances within the body. When a receptor molecule is stimulated by the presence of a hormone, it results in a particular physiological response. Hormone release in the pituitary gland contributes to body growth, predominately the growth of long bones.

Somatostatin inhibits prolactin release, a hormone that causes mammary glands in women to grow after giving birth.
Somatostatin inhibits prolactin release, a hormone that causes mammary glands in women to grow after giving birth.

Growth hormone is controlled by GHRH, which is a 44-amino-acid peptide that is created by neurons in the arcuate nucleus found in the hypothalamus. When GHRH is released, it is moved from the hypothalamus into the anterior pituitary gland via a hypothalamic-pituitary system, resulting in a release of growth hormone from somatotrophs into the bloodstream. Somatotrophs are membranous cells found in the anterior pituitary that specifically produce growth hormone.

Hormone release in the pituitary gland contributes to body growth.
Hormone release in the pituitary gland contributes to body growth.

Somatostatin, or growth-hormone-inhibiting-hormone (GHIH), is a 14-amino-acid peptide that inhibits the release of growth hormone in the body. It is extensively spread throughout the central nervous system, but the inhibiting nerve cells are located in the periventricular nucleus in the hypothalamus. Many neurons located in the arcuate nucleus contain somatostatin, which also inhibits prolactin release, a hormone that causes mammary glands in women to grow before and after giving birth.

Release of growth hormone within the body causes cell division and results in the development of body tissues. Growth hormone has a significant effect on body growth, particularly during perinatal growth and throughout adolescence. Throughout these periods, variables such as fasting, stress, and exercise all increase growth hormone release, which act to make fatty acids into energy.

Discussion Comments

anon305436

GHRH is not only a peptide when 29 or more amino acids are bonded. It is as it states a Growth Hormone Releasing Hormone. GHRP is peptide like Sermorelin or GHRP-2 and 6. Now CJC-1295, also known as GRF 1-29, modified is a hormone sequence that releases GH at a rate of 30 minutes post subcutaneous injection where the peptides are only capable of a seven-minute release of GH.

There are many functions that are enhanced by GH release. The body's metabolism increases, the IGF-1 is elevated and therefore anabolism takes place and muscle increases as adipose fat is absorbed and used as fuel.

There is also a profound ability to heal faster from injury and the immune system is also strengthened to levels of childhood proportions.

If you want muscle and loss of fat or just a youthful life of retarding the aging process, then GHRH analogs might be for you. You must be able to self-administer a tiny shot from a 29-gauge needle in the belly nightly to receive benefits. The cream is crap and does almost nothing at all.

discographer

@ddljohn-- What you said makes sense, but don't forget about somatostatin, that's the other side of the triangle.

I don't think we can really have too much GHRH because there is a limited supply. We are constantly producing, using and storing GHRH based on our needs. If the need for GHRH increases, we will just end up using all of our GHRH storage. To keep this all in balance, we have somatostatin which shuts off the use of GHRH.

All of this work is so that we can have growth hormone. If the system doesn't work like it should, people can be treated with either of these peptides or with growth hormone therapy.

I was treated with GHRH for a short time because of a metabolic problem. It was in a topical cream form and was absorbed by my skin.

ddljohn

@fify-- If you look back at the article, GHRH is not a hormone, it's a peptide. It's the required step before human growth hormone and of course, there could be problems with it. If the hypothalamus produces too much GHRH, there will be too many growth hormones entering the blood stream. So this could lead to excessive growth, but other problems in the body too.

Don't think of GHRH as having to do with growth only. GHRH also affects our sleep, how we metabolize proteins and carbohydrates and even in the function of our pancreas and intestines. So if there is excessive or not enough GHRH being produced, it could affect all these different systems.

fify

Sometimes on TV, they show really big and tall people. I remember on one show, they introduced the tallest man in the world who was from China, I believe. Do people who are excessively tall, have a problem with their GHRH? Are they tall like that because their body produces too much GHRH which causes them to keep growing?

I suppose it could also be due to not enough somatostatin right? GHRH might be working right, but the somatostatin might not be inhibiting GHRH.

I'm also really surprised to know that stress can actually increase GHRH and cause us to grow during adolescence. I thought it would do exactly the opposite. That's interesting.

Post your comments
Login:
Forgot password?
Register:
    • GHRH is released from the hypothalamus.
      By: stockshoppe
      GHRH is released from the hypothalamus.
    • Somatostatin inhibits prolactin release, a hormone that causes mammary glands in women to grow after giving birth.
      By: WavebreakmediaMicro
      Somatostatin inhibits prolactin release, a hormone that causes mammary glands in women to grow after giving birth.
    • Hormone release in the pituitary gland contributes to body growth.
      By: CLIPAREA.com
      Hormone release in the pituitary gland contributes to body growth.