Stimulation of growth hormone secretion with human growth hormone releasing factors (GRF1-44, GRF1-40, GRF1-29) in normal subjects.
Losa. M M; Schopohl. J J; Müller. O A OA; von Werder. K K
Key Findings
- All tested GRF peptides (44, 40, and 29 amino acids) raise GH levels similarly after a 50 µg IV bolus.
- Peak GH occurs 15‑30 min post‑injection with no serious side effects reported.
- Repeating a 50 µg GRF1‑29 dose every 6 hours still produces robust GH spikes, unlike continuous infusion which can cause desensitization.
Practical Outcomes
- For self‑experimenters, a 50 µg sub‑cutaneous (or IV) dose of sermorelin can be used to acutely boost GH, with effects lasting about half an hour. Scheduling doses every 6 hours appears to maintain responsiveness, offering a simple protocol for short‑term GH elevation without apparent safety concerns.
Summary
Giving a single 50 µg dose of the short growth‑hormone‑releasing peptide (GRF1‑29, also known as sermorelin) causes a clear spike in growth hormone within 15‑30 minutes, and this effect repeats safely when the dose is given every 6 hours.
Abstract
Peptides of different chain lengths (GRF1-44, GRF1-40, GRF1-29) were given as a 50 micrograms i.v. bolus to five normal volunteers. Blood was collected before and until 120 min after GRF injection. No serious side effects were recorded. All GRF peptides led to a clearcut and significant increase of GH levels compared to placebo controls with the maximum occurring 15-30 min after GRF injection. There was no significant difference in the maximal GH increase after the different GRF peptides. When GRF1-44 was administered to five normal subjects over 2 days in 6- and 18-h intervals, respectively, significant increase of GH levels were recorded after each injection compared to placebo controls. Again, there was no significant difference between the maximal GH rises during the different tests. These findings show that the short GRF1-29 peptide may be used for diagnosis and therapy. In addition, in contrast to continuous infusion and administration of GRF in short intervals, GRF application in 6-h intervals leads to adequate GH responses.
Study Information
pubmed
1984
1984-12-03T00:00:00.000Z
10.1007/bf01782473