Hi, so in this lecture we will be learning about how the growth hormone behaves or like how it functions. So the growth hormone is basically responsible for controlling the functions of muscles like consumption of glucose in the muscles. Then if I say liver it is responsible for fat metabolism for stimulating the process of fat metabolism.
Then in other body parts in body tissues. for their growth process in kidneys again for so every irrespective of the fact that it is not controlling the growth of brain and the eye so these are some of the parts where it is controlling the function and in this lecture we will be learning how growth hormone is actually giving out its mechanisms to affect the target cells right so what is growth hormone doing i told you in the previous lecture that hypothalamus is responsible for controlling the release of growth hormone which is the master of the master gland. So hypothalamus is releasing two hormones. Either it is releasing GHIH or is it releasing GHRH.
So a brief difference between the two of them is GHIH stands for growth hormone inhibitory hormone and GHRH stands for growth hormone releasing hormone. So whenever there is a condition which demands a suppression of this mechanism, then obviously GHIH would be released and this in turn would be inhibiting the activation of anterior pituitary which would be stopping the body growth but let's discuss about the fact of what is happening here so how is GHRH released once come to that point so any condition like a stress condition or fasting condition or exercise So these are some of the stimulatory factors which are activating the hypothalamus or which are giving hypothalamus that yes, the body is in need of the release of growth hormone. So these are some of the factors which are stimulating the hypothalamus to release growth hormone, releasing hormone. And growth hormone, releasing hormone is targeting its side which is the anterior part of the pituitary.
So this is targeting the anterior pituitary region, not the posterior pituitary region. anterior pituitary region is now so this this its target site is this region so here it would be releasing growth hormone fine growth hormone has now specific sites to work on first of all so this is all a stimulatory process like when this is happening this is this chain is being followed when when there is a that the growth hormone levels are up to the mark and these processes are not happening these situations are not there then there would be a suppression of the entire process So when hypothermia is stimulated it releases growth hormone releasing hormone which in turn activates the anterior pituitary which releases a growth hormone. Now the growth hormone it targets liver which is releasing IGF-1 and IGF-2.
Now what is this IGF-1 and IGF-2? These stands for insulin growth factor 1 and insulin growth factor 2. So liver is releasing IGF-1 and IGF-2 which in turn are binding to different parts of the body where the growth has to happen like this is controlling the metabolism and this is stimulating the metabolism by releasing these factors so like the body tissues and the bone are the target size that IGF-1 and IGF-2 are being released they bind to these sites and bring about the stimulation of metabolism the body growth the tissue growth bone length growth everything which is happening here is because these factors are being released after growth hormone was hitting the liver area and then growth hormone is also directly binding it is releasing it is binding to liver which is releasing igf-1 and igf-2 on the other hand it is also directly binding to these sites where again the growth processes happen so these are the two processes through which the growth hormone is binding to its site which releases some factors and on the other hand it is also directly binding to its target sites one thing i want to share here that how is this process happening so that whenever the growth hormone is being released there is an increased production of camb okay so whenever the growth has to happen the metabolism would be stimulated there would be increased releases of camb metabolism processes would be stimulated glucose uptake would be initiated you can also add muscles here Muscles would be taking more uptake of the glucose, there would be fat metabolism, every metabolism would be stimulated and finally the growth will happen. But if the growth process has to stop, then like in the case the body is already growing to a certain point, it does not require the growth hormones, then the growth hormones would be up to the mark and it will give out an inhibitory signal to the hypothalamus which is acting as a detector here.
So one most important point which we will be learning about in the near lectures is that hypothalamus is a detector which detects easily that which hormone level is up to the mark or not up to the mark and when I say up to the mark it means to the required levels which it has to be in the blood. So the hypothalamus would be giving out inhibitory signals in the form of growth hormone inhibitory hormone which is inhibiting the anterior bitumtri to stop the release of growth hormone but when these conditions are prevailing They are giving a stimulatory signal to hypothalamus which releases growth hormone, releasing hormone which activates the anterior pituitary which stimulates the release of growth hormone which binds to liver which releases insulin growth factors 1 and 2 which increase the metabolism of these areas. Body growth happens here, hyperplasia happens here, fat metabolism is stimulated. These are the responses of the growth hormone. These are the physiological responses of the growth hormone.
and in all this process the cmp production is increased so this is the growth hormone functioning that i was discussing in the next lecture we'll be talking about