GHRP-6
Growth Hormone Releasing Peptide-6, Growth hormone-releasing hexapeptide, His-D-Trp-Ala-Trp-D-Phe-Lys-NH2
New diagnostic tests of GH reserve.
Martul. P P; Pineda. J J; Pombo. M M; Peñalva. A A; Bokser. L L; Dieguez. C C
Key Findings
- Dexamethasone, galanin, and GHRP‑6 all trigger GH release, but the response is blunted in obesity and GH insufficiency.
- GHRP‑6 produces a potent GH surge in healthy children, higher than the other two stimuli.
- Because some GH‑insufficient individuals show GH levels similar to normals, these tests (including GHRP‑6) have limited diagnostic specificity.
Practical Outcomes
- For biohackers, the data confirm that GHRP‑6 can robustly stimulate GH, but its effectiveness may be reduced in people with excess body fat. It suggests that using GHRP‑6 for GH boosting might work best in lean individuals, and that response variability should be expected. No new dosing protocol emerges, but the study warns that obesity can blunt the GH‑boosting effect.
Summary
The study tested three new ways to see how much growth hormone (GH) the body can still make, using dexamethasone, galanin, and the peptide GHRP‑6. All three worked well in healthy kids, but the response was much weaker in kids who were obese or had GH deficiency. GHRP‑6 gave the strongest GH boost in normal children, but its effect overlapped with the low‑responders, making it less useful as a diagnostic tool.
Abstract
Pharmacological tests are essential for the diagnosis of growth hormone (GH) insufficiency. Obesity is a pathological state associated with blunted GH response to all the classical stimuli tested. In the present study, three new pharmacological stimuli for GH reserve were evaluated in three groups of subjects: Normal, GH-insufficient and normal growing obese children. Dexamethasone provokes a clear GH-response in normal children, whereas the response in the other 2 groups of patients is significantly diminished. Galanin-induced GH-secretion is significantly higher in normal than in obese children. GHRP-6 causes a potent GH release in normal children, higher than in GH-insufficiency or obesity. The overlap shown between GH-insufficient patients and normal children reduces the usefulness of the tests. Similar to the classical stimuli, the response to these new tests is also decreased in obesity.
Study Information
pubmed
1993
10.1515/jpem.1993.6.3-4.317