Maintaining endogenous GH release with IPA/CJC during exogenous GH supplementation. Leveraging natural and exogenous GH.

[Wilson6]

Have too much time on my hands so I was thinking more than I usually do. Using CJC (no DAC)/IPA combo increases natural GH release, probably to the point of what 1 - maybe 2 IU of rHGH would produce, assuming young and natural production is intact. Exogenous androgens suppress endogenous production of testosterone, that can be mitigated to some degree with concurrent hCG administration. I wonder if, the same could be done with CJC/IPA used in combo with exogenous GH? Basically leveraging the effects of a lower dose of rHGH while still producing at least one burst of nighttime endogenous release with a pm inj of CJC/IPA. Thoughts? Anyone tried this or used CJC/IPA to restart natural GH production after a round of rHGH or alternated the two nightly? I do not know of any study that has ever addressed this.

 

[Bigtex]

Have too much time on my hands so I was thinking more than I usually do. Using CJC (no DAC)/IPA combo increases natural GH release, probably to the point of what 1 - maybe 2 IU of rHGH would produce, assuming young and natural production is intact. Exogenous androgens suppress endogenous production of testosterone, that can be mitigated to some degree with concurrent hCG administration. I wonder if, the same could be done with CJC/IPA used in combo with exogenous GH? Basically leveraging the effects of a lower dose of rHGH while still producing at least one burst of nighttime endogenous release with a pm inj of CJC/IPA. Thoughts? Anyone tried this or used CJC/IPA to restart natural GH production after a round of rHGH or alternated the two nightly? I do not know of any study that has ever addressed this.

We have to start out with Somatostatin, also known as growth hormone-inhibiting hormone. So somatostatin works in a negative feedback loop to prevent the pituitary from over pulsing GH. So when IGF-1 levels start rising above what is normal, somatostatin pulses to slow down the pulse of GH and return the body to homeostasis. Now when you do rhGH somatostatin works the same way but the pituitary almost stops the production of endogenous GH because blood levels remain high even after the pituitary stops GH pulses. There is evidence that GHRPs works as a functional somatostatin antagonist at pituitary level. Thus, allowing the pituitary to function normally, even on rhGH. It also prevents the pituitary shut down while using GRFs allowing the body to naturally product larger amounts of GH without shutting down the pituitary pulses.

 

[Wilson6]

We have to start out with Somatostatin, also known as growth hormone-inhibiting hormone. So somatostatin works in a negative feedback loop to prevent the pituitary from over pulsing GH. So when IGF-1 levels start rising above what is normal, somatostatin pulses to slow down the pulse of GH and return the body to homeostasis. Now when you do rhGH somatostatin works the same way but the pituitary almost stops the production of endogenous GH because blood levels remain high even after the pituitary stops GH pulses. There is evidence that GHRPs works as a functional somatostatin antagonist at pituitary level. Thus, allowing the pituitary to function normally, even on rhGH. It also prevents the pituitary shut down while using GRFs allowing the body to naturally product larger amounts of GH without shutting down the pituitary pulses.

Thanks BT. Do you have any references on the GHRPs and overriding somatostatin? Haven't found anything yet. Only paper was by Rosenthal et al, 1985 JCI, they found after GH treatment, there was a blunted response to GRF. Another in children with intact GH/IGF-1 systems given GH for 6 mo. It took 48 - 60 hrs for their endogenous GH to normalize. Appears to be much shorter than the HPTA for endogenous androgens.

 

[Bigtex]

Gene Transcription of Receptors for Growth Hormone-Releasing Peptide and Somatostatin in Human Pituitary Adenomas1

abstract. Growth hormone (GH)-releasing peptides (GHRP) or secretagogs (GHS) constitute a family of synthetic compounds with potent and specific GH releasi

academic.oup.com

Nielsen S, Mellemkjaer S, Rasmussen LM, Ledet T, Astrup J, Weeke J, Jørgensen JO. Gene transcription of receptors for growth hormone-releasing peptide and somatostatin in human pituitary adenomas. J Clin Endocrinol Metab. 1998 Aug;83(8):2997-3000. doi: 10.1210/jcem.83.8.5046. PMID: 9709982.

" GHRPs act both at the hypothalamic and the pituitary level through mechanisms involving amplification of GH-releasing hormone activity and functional somatostatin antagonism."

This is why it is so important to use a GHRP with a GHRH. Continued use of say tetra substituted GRF 1-29 could eventually cause somatostatin to rise enough to slow or stop the pituitary from pulsing GH. Just like rhGH.

Pimentel-Filho FR, Ramos-Dias JC, Ninno FB, Façanha CF, Liberman B, Lengyel AM. Growth hormone responses to GH-releasing peptide (GHRP-6) in hypothyroidism. Clin Endocrinol (Oxf). 1997 Mar;46(3):295-300. doi: 10.1046/j.1365-2265.1997.1270942.x. PMID: 9156038.

Growth hormone responses to GH-releasing peptide (GHRP-6) in hypothyroidism - PubMed

We have shown that patients with primary hypothyroidism have higher GH responses to GHRP-6 than to GHRH, which are markedly blunted. When GHRP-6 was associated with GHRH, a significant increase in the GH response was observed in these patients, which could suggest a role for somatostatin in this...

pubmed.ncbi.nlm.nih.gov

" but there is evidence that this peptide acts as a functional somatostatin antagonist at pituitary level. "