How Does Growth Hormone Affect Various Organs In Body?
I understand GH declines at the end of puberty, and our internal organs also stop growing at the same time.
Let's suppose internal organs hasn't reached its genetic size yet, and GH has already declined....will the organ still achieve its genetic size via other hormones despite low circulating GH?
Hope you can advise.
Final growth is still achieved
Detailed Answer:
Hi
Welcome to Healthcare-Magic
Greetings of the day
Dear Mr Roni
Growth Hormone is only one of the hormone required for growth. It is a general trophic hormone. Apart from growth hormone many of the organs have additional trophic hormones which help in their growth including internal organs. For example
1. Skin has Epidermal growth factor(EGF)
2. Bones : Testosterone, Osteoblast stimulating factor
3. Liver: Insulin like growth factor, Endothelin proliferating factor
In short Growth hormone acts directly and facilitates action of other trophic hormones and achieves growth.
During puberty there is surge of many hormones which help in growth
Every organ is genetically programmed to achieve its pre-defined growth. If there is decline in growth hormone, other trophic hormones act and cause the growth
Do get back to me if you need any further assistance, will be glad to assist you.
Take Care
Best Regards
Dr Deepak Kishore
MBBS,MS,MCH
Thanks for the welcome and for valued answers.
I have a final query regarding androgen receptors. Of course androgens in puberty cause changes such as in growth, hair, and voice, via the androgen receptor at various sites.
Do androgen receptors exist at these sites in young boys also...ie if high androgens were somehow present in a young boy( hypothetically speaking) he would also experience hair and voice changes?
Do androgen receptors always exist as long as cell exists..regardless of age of boy?
Wishing you all the best,
Kind Regards.
XXXX
Androgen receptors are always present
Detailed Answer:
Hi
Greetings
Only certain organs of the body are androgen sensitive. Means they have receptors which respond to androgens. The receptors are present always in these tissue and are stimulated by androgens. Up regulation or down regulation can occur, but the receptors are always present.
At time of puberty when there is LH/FSH surge: LH acts on Leydig cells of Testis causing release of androgen(other source of androgen is adrenal cortex_ it secretes androgens in samll quantity even before puberty) which acts on androgen receptors causing development of puberty.
I hope I have answered your query.
Wish you happy and healthy life
Take Care
Regards
Dr Deepak
Thanks again for your valued advice.
So as long as the receptors and androgens are present, we should have a binding?
Is it possible for both to be present , and still not have a binding due to receptor insensitivity to androgen?
Wishing you all the best success and happiness
Kind Regards
XXXX
It occurs only when receptors are defective
Detailed Answer:
Hi
Receptor insensitivity only occurs in genetic syndromes in which receptors are defective and androgen fails to produce any action. This is known as Androgen insensitive receptors.
Take care
Best Regards
Deepak
Thanks again. In valued advice above, receptor are present always in these tissue and are stimulated by androgens. Up regulation or down regulation can occur, but the receptors are always present.
What does up regulation and down regulation mean in this case?
Im worried it could mean 'densensitizing' of the receptors, which means same as AIS genetic syndrome
Wishing you all the best.
Kind Regards
XXXX
Explained below
Detailed Answer:
Hi
Greetings,
When the concentration of androgen hormone increases: there is initially increase in normal of receptors which occurs due to synthesis and recruitement of new receptors. Further increase in androgen concentration beyond certain limit causes decrease in further inception of new receptors due to negative feedback mechanism.
This is important to prevent hyper stimulation and is a protective mechanism.
It is not desensitizing the receptors.
Take Care
Best Regards
Dr Deepak