Diagnostic & mechanistic studies
tested Serum GH pulse characteristics (peak/trough, spectral analysis, serial array averaging) during spontaneous and clamp conditions
result Continuous GHRH amplified peak GH in normals (21.1→62.0 mU/l, P=0.008); combined GHRH+SS produced regular pulses. Irradiated adults: GHRH amplified GH (4.2→6.5 mU/l) but far below controls.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested Height velocity, height SDS for bone age, IGF-I levels, GH response to IV/SC GHRH stimulation
result Height velocity increased ≥2 cm/yr in 41/43 children. HD GHRH comparable to GH group; LD lowest. Height SDS for bone age improved only in GH group. LD showed GH-axis priming; HD showed GHRH accumulation.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested Height velocity at 6 months; IGF-I; GHRH antibody formation
result Height velocity: GHRH 30µg=9.2 cm/yr, GHRH 60µg=9.3 cm/yr vs GH=14.6 cm/yr (p<0.01). IGF-I rose then fell to pre-treatment levels. GHRH antibodies in 39/40 patients.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested Nocturnal GH pulsatility, IGF-I, IGFBP-3, GHBP, body composition, skin thickness, insulin sensitivity, lipids, quality of life
result Nocturnal GH↑ in women (P<0.01) and men (P<0.05); IGF-I↑ and IGFBP-3↑ within 2 weeks; lean mass↑ men only (P<0.05); insulin sensitivity↑ men (P<0.05); skin thickness↑ both (P<0.05); well-being↑ and libido↑ men (P<0.05/0.01).
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested immune cell subsets, lymphocyte function, GH pulsatility, IGF-I, IL-2, soluble IL-2R
result GH secretion +107%/+70% (men/women), IGF-I +28%; B cells +30%, T cell receptor α/β +20%, γ/δ +40%; IL-2R (CD25) +70%; mitogen responses +50%; no adverse effects.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Basal GH levels and GH delta area under the curve after GHRH challenge under low vs high FFA conditions
result Acipimox (↓FFA): GH delta area 2937 vs 1154 µg/L×120min (P<0.01); lipid infusion (↑FFA): GH delta area 2498 vs 4512 µg/L×120min (P<0.01). FFA control preserved in acromegaly.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Peak GH concentration and AUC GH over 2 hours post-stimulation
result At 0.15 µg/kg: median peak GH 4.5 vs 37.4 mU/l (P<0.01); at 1.0 µg/kg: 4.8 vs 15.2 mU/l (P<0.05); incremental dose-response preserved in irradiated group (AUC 122→179→268 mU/l·min, P=0.007).
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Peak GH response (µg/L) to GHRH or hexarelin after various pre-treatments
result GHRH pre-treatment did not blunt GHRH response (16.7 vs 15.1 µg/L); rhGH inhibited GHRH response (8.7 vs 38.8 µg/L, p<0.001); rhGH blunted hexarelin response (34.1 vs 51.2 µg/L, p<0.05).
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested height velocity during and 6 months after GHRH treatment
result Both ISS and GHND groups showed significant growth rate increases during treatment; 6 months post-discontinuation, growth rates were not significantly above pre-therapy baseline in either group.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested height velocity, height SDS, bone age; GH response to provocative GHRH testing as predictor of subsequent GH therapy response
result 25/27 withdrew from sermorelin trial due to inadequate HV; GH response to provocative GHRH testing at 6 and 12 mo inversely correlated with first-year growth on Saizen.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Peak serum GH response; concordance between tests; discrimination between GHD and non-GHD patients
result 12/22 irradiated patients GHD by both tests. Mean GH peak after GHRH+GHRP-6 was 6.2±0.8 μg/L in GHD subgroup; larger GHD vs non-GHD differential vs ITT; 2 discordant responses.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Peak GH response to GHRH with vs without galanin co-infusion
result Galanin did not reverse blunted GH response in hyperthyroid patients (GHRH+saline 10.2±2.5 vs GHRH+galanin 12.5±3 µg/l); normals showed augmented response (20.7±4.8 vs 43.8±6 µg/l).
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested plasma GH levels at 0, 15, 30, 45, 60, 90, 120 min post-injection
result Normal children peak GH 80.31±19.28 ng/ml at 45 min; GH-deficient peak 13.10±10.78 ng/ml (P<0.01 lower); 21.4% of GHD had half-response suggesting hypothalamic origin.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested 24-h GH profiles, IGF-I levels, iv GHRH stimulation response
result High dose (1 mg bid) significantly increased mean 24-h GH, AUC, peak amplitude, and IGF-I (all P<0.05) in old men to levels not significantly different from young men; low dose 0.5 mg showed no significant effect.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested Serum GH and IGF-1 levels, safety, tolerability, glucose tolerance, anti-GHRH antibodies
result PEG-GHRH produced clear GH increase vs placebo in both groups; single-dose effect persisted 12h in young; sustained GH increase on repeated dosing in elderly; IGF-1 also increased.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH peak response to GHRH after pharmacological pretreatment with adrenergic/cholinergic modulators
result Clonidine+pyridostigmine enhanced GH response (P<0.01); atropine blocked it (P<0.01); clonidine overcame atropine inhibition (P<0.05); yohimbine blunted pyridostigmine enhancement (P<0.05).
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH peak response after pretreatment and provocation combinations
result Pyridostigmine enhanced GH response to GHRH in normals (median peak 32.7 vs 1.8 µg/l) and group B diabetics (29.3 vs 4.4 µg/l), but not in group A diabetics with exaggerated baseline responses (39.9 vs 35.7 µg/l).
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Pattern of GH secretion (peak amplitude, frequency, interpulse values) by RIA and cluster analysis over 10-hour sampling period
result GRF infusion augmented GH peak amplitude without changing frequency; clonidine pretreatment significantly increased total GH secreted, raised peak count, and shifted secretion to a more physiological episodic pattern.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested peak and integrated plasma TSH and PRL levels
result GHRH+TRH produced larger peak and integrated TSH and PRL vs TRH alone; GHRH alone had no effect on TSH and only modest effect on PRL.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH response to GHRH challenge following clonidine pretreatment at varying intervals
result Clonidine 60–120 min before GHRH significantly (P<0.01) enhanced GH responses vs GHRH+placebo; alpha 2-agonism acts by inhibiting hypothalamic somatostatin release, not stimulating GHRH secretion.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested plasma somatostatin-like immunoreactivity (SLI) at baseline, after acute bolus, and after 3 and 6 months of therapy
result No significant acute SLI change after bolus. Basal and nocturnal SLI rose after 3 months of GHRH(1-29)-NH2 therapy and remained elevated at 6 months; possible enteroinsular axis source.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested serum GH response across GHRH dose range with/without cholinergic enhancement
result PD enhanced GH response at all GHRH doses; 1.0, 0.3, 0.1 µg/kg elicited similar GH peaks after PD; 0.01 µg/kg still raised GH above saline after PD.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Mean serum GH levels (spontaneous and GHRH-stimulated) by day and night; pulse number
result GHRH raised mean GH by day 17.7 vs 2.2 mU/l and night 26.9 vs 5.5 mU/l (p<0.05). Pyridostigmine failed to augment spontaneous or GHRH-stimulated GH overall; brief morning rise 4.4 vs 2.4 mU/l noted.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Proportion and amount of 22K-hGH vs 20K-hGH secreted; clearance half-lives of each variant
result Repetitive stimulation reduced 22K-hGH released; 20K-hGH unchanged, increasing 20K proportion (P=.05). Half-lives of 20K vs 22K-hGH not significantly different (P=.55).
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested short-term memory (word recall) and GH secretion
result GRF group recalled more words: A2 list 14.76±1.55 vs 11.83±1.34 (p<0.01); B list 12.17±1.68 (p<0.005). GH peaked at 28.15 ng/ml at 15-30 min (EG1) and 15.52 ng/ml at 45 min (EG2).
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested growth velocity, 24h GH profiles
result Mean growth velocity increased from 4.6 to 7.0 cm/year (P=0.04) in 5 children treated 1 year; sustained pulsatile GH augmentation without desensitization.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested maternal and fetal serum hGH, maternal hPGH, and cord serum GRF-(1-29)-NH2 concentrations at birth
result GRF elicited small rise in maternal hGH (P=0.08); hPGH unaltered; cord hGH similar to controls; GRF undetectable in cord serum, suggesting no transplacental passage.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested diagnostic accuracy for AGHD (peak GH, ROC AUC) as reference standard
result Arginine+GHRH(1-29)NH2 [sermorelin] served as active comparator reference; macimorelin showed comparable diagnostic accuracy; specific peak GH numbers for sermorelin arm not reported.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Peak GH, GH AUC, AUC of instantaneous secretion rate (ISR), half-secretion time; regression on BMISDS and age
result PWS children had significantly higher peak GH and AUCGH than adults; lower half-secretion time in children. BMISDS negatively correlated with AUCGH in DEL15 (p<0.0001); age drove secretion delay (p<0.001).
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested peak GH response, area under GH curve, peak GHRH immunoreactivity, plasma disappearance rate
result 3 µg/kg SC: peak GH and AUC similar for both peptides; no significant differences in PK; 'superactive' potency of agonist analogue seen in rat not replicated in humans.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested GH secretion and growth velocity at 3 and 6 months
result All 8 children showed augmented GH secretion and increased growth velocity after 3 and 6 months of continuous subcutaneous GHRH (1-29)NH2 therapy.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested 24-hour GH secretion parameters, pulsatile GH restoration
result Pulsatile GH restored in all 3 children on 40 mcg/kg/day, 1/3 on 20 mcg/kg/day. All 24h GH parameters increased; response attenuated by day 21 in 5/6 children.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Detection of Geref metabolite GHRH3-29 in human plasma post-subcutaneous injection; method validation for anti-doping sports testing
result GHRH3-29 (Geref metabolite) confirmed in plasma of one healthy male volunteer after subcutaneous injection; LLOD <50 pg/mL; recovery 19–37%; imprecision <20%.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH pulse patterns during infusion; GH response to bolus after infusion vs control
result GH pulses up to 80 mU/l throughout 10h infusion; post-infusion bolus response blunted vs control (peak 59.0±44.8 mU/l); 2/4 subjects near-flat response, 2/4 confounded by GH peak.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH response to GRF 1-29 under dopaminergic, alpha-adrenergic, cholinergic, and TRH blockade
result Dopaminergic (MCP) and alpha-adrenergic (THYM) blockade had no effect on GH response to GRF. TRH did not modify GH response. Atropine significantly reduced GH responses to GRF.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH response to GRF 1-29 with vs without cholinergic blockade
result Pirenzepine did not alter GH responses to GRF 1-29 (1 µg/kg) or TRH in 8 acromegalic subjects; somatotroph adenomas appear disconnected from hypothalamic cholinergic control.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested serum GH levels over 120 minutes post-insufflation
result Peak GH 28.3 ± 12.0 ng/ml at 15 min (range 17.1–47.6); delta GH 27.0 ± 12.2 ng/ml; levels still significantly elevated at 120 min (p<0.05).
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Peak GH response (max GH) over 120 min; correlation with sleep GH, somatomedin C, age, sex, puberty
result Max GH >10 ng/ml = normal. 3/86 non-GHD fell below; 11/45 GHD exceeded threshold. In GHD, max GH inversely correlated with age. GRF(1-40) and GRF(1-29)NH2 gave identical results.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested Serum IGF-1 level (primary); also T, FT, estradiol, LH, FSH
result Mean IGF-1 rose from 159.5 to 239.0 ng/mL (p<.0001) over mean 134 days; co-admin of aromatase inhibitor/tamoxifen attenuated the IGF-1 increase.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested peak GH response and AUC of GH response to GRF
result T4 replacement increased peak GH (17.0±2.8 vs 32.6±5.7 mU/l, P<0.02) and AUC (51.7±14.3 vs 101.5±28.1, P<0.02) to GRF in 9-10/14 patients.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Peak GH response and AUC after GHRH stimulation; plasma FFA levels
result Acipimox restored GH peak in hyperthyroid patients from 9.6 to 25.9 µg/L (matching controls' 25.7); AUC rose from 12.9 to 41.1 µg/L×2h, exceeding controls' 28.7. FFA reduction mediated the effect.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH, ACTH, cortisol, prolactin, TSH, LH, FSH responses
result Galanin alone: GH peak 11.3±2.2 µg/l; galanin+GHRH: GH peak 49.5±10 µg/l vs GHRH alone 24.3±5.2 µg/l; slight ACTH/cortisol suppression.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH peak and area under curve; LH and FSH peak after GnRH
result GH peak: GHRH alone 14±5 μg/L, galanin alone 7.3±1.2; GHRH+galanin 31.4±4.4 μg/L (significantly enhanced vs either alone); galanin did not significantly raise LH or FSH.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Peak delta GH response (µg/L)
result GHRH alone blunted in GC-excess pts (median deltaGH 0.9 vs 7.1 µg/L controls); hexarelin alone not blunted (15.5 vs 17.9 µg/L); hexarelin bypasses somatostatin inhibition.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Serum GH response to GHRH(1-29)NH2
result No overall change in serum GH response to GHRH(1-29)NH2 after 1 year of octreotide treatment; used as a provocation test, not therapy.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH, IGF-I, TSH, T4, free T4, free T3, PRL, ACTH, beta-endorphin, cortisol, IGFBP-3, CBG responses to simultaneous hypothalamic hormone challenge
result HA men (n=12) showed exaggerated GH response to GHRH and significantly elevated IGF-I vs SL men; lower basal ACTH; blunted beta-endorphin response to oCRH; elevated basal cortisol + CBG.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested peak GH secretion following GHRH-(1-29) stimulation
result GHRH-(1-29) GH response was significantly lower than hexarelin in idiopathic GHD; varied from normal to absent in anatomical GHD; absent/blunted in hypothalamic-pituitary disconnection.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH peak response to GHRH during galanin vs saline infusion
result GH peak after GHRH+galanin in Cushing's: 2.3±0.6 µg/L vs saline 1.2±0.4 µg/L (NS); controls: 51.4±9.8 vs 24.6±4.6 µg/L (p<0.05). Galanin failed to enhance GHRH response in Cushing's.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested growth velocity (cm/yr), bone age advancement
result 68.7% responders; growth velocity 3.4→6.8 cm/yr at 6 mo, sustained at 6.2–6.6 cm/yr through 24 mo. Bone age advanced proportionally to treatment duration.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested plasma GH response after priming vs baseline acute GHRH test
result Responders (n=8): GH rose 6.0→18.0 ng/ml (p<0.001); non-responders (n=8): no change (5.5→6.2 ng/ml, p=NS). Priming separated hypothalamic from pituitary GHD.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Serum GH concentration-time parameters (peak GH, rate of rise/decline, time to peak, GH at 2h)
result 10 µg and 100 µg produced significant peak GH (24.03 vs 26.09 mU/l); 100 µg delayed peak to 24.8 min and GH remained elevated at 2h (5.01 mU/l vs saline 0.98 mU/l, p<0.001).
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested Height velocity, overnight GH profiles, IGF-I, fasting glucose/insulin, final height prediction
result HV increased from 4.8 cm/yr pre-treatment to 7.2 cm/yr at 12 months (P=0.001); final height prediction +3.4 cm; catch-down growth after cessation.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested metabolic clearance rate and disappearance half-time
result D-Ala2 analog MCR 21±1.2 vs 39.7±3.9 mL/kg.min (P<0.001); half-time 6.7±0.5 vs 4.3±1.4 min (P<0.05) — reduced clearance, longer half-life.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Peak and integrated serum GH, cortisol, PRL, IGF-I; deconvolution of GH secretory pulse amplitude and frequency
result GHRH raised peak GH to 7.6±1.3 µg/L vs placebo 1.2±0.2; increased pulse amplitude 4-fold and pulse count (4.4±0.3 vs 2.6±0.5); IGF-I unchanged. Both L-692,429 doses exceeded GHRH response.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH peak after GHRH under varying cortisol levels
result GH peaks suppressed at cortisol ≥700 nmol/L (25 mg HC: 70±11%, 250 mg HC: 69±7% of saline-normalized baseline); 12.5 mg HC (413 nmol/L) did not differ from saline.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH response to GHRH stimulation; insulin and C-peptide response to 75-g oral glucose tolerance test
result 6 MD patients responded normally (GH peak 17.1±1.46 µg/l) vs controls (27.8±19.6 µg/l, NS); 6 responded subnormally (peak 3.15±1.46 µg/l, P<0.001). GH response negatively correlated with insulin response (r=-0.79, P<0.001).
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH peak response after GHRH stimulation
result Lean T2D: blunted GH after GHRH+PD vs lean controls (15.77±2.17 vs 40.88±6.17 µg/L, P<.05); PD enhanced GH in obese diabetics, obese controls, non-obese controls but not lean T2D.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH peak response to GHRH under hypercortisolism and adrenergic/cholinergic modulation
result DEX blunted GH peak (10.7 vs 20.3 µg/L). PRO+DEX reversed inhibition (39 µg/L); CLO+DEX partial (25.9); PD+DEX did not reverse (12.9). Suggests DEX acts via enhanced β-adrenergic somatostatin tone.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH peak response variability with/without pyridostigmine co-administration
result GHRH-alone GH peaks: 14.2, 15.3, 16.5 µg/L (CV 65–102%); PD+GHRH peaks: 31.9, 44.8, 49.9 µg/L with reduced variability.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH release (peak mU/l), PK parameters, bioavailability, nasal vs IV potency comparison
result IV 0.25 µg/kg elicited significant GH release; max ~90 mU/l at 1–2 µg/kg IV. Intranasal bioavailability 3–5%; 50 µg/kg IN ≈ 1 µg/kg IV potency. GH elevation sustained ~3h post-IV.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested GH secretion (plasma peaks), knemometric growth rate, stadiometric height velocity, antibody development
result GH peaks 10–85 mIU/l on day 1; knemometric growth rate doubled at 6 weeks (0.24→0.48 mm/wk, p=0.03) then declined; 6-month height velocity did not increase; antibodies in 3/8 at 6 weeks.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested 24-hour GH profiles (integrated concentration, pulse amplitude/frequency) and height velocity
result Biphasic response: integrated GH conc rose 1.6→3.5 µg/l/min early, then fell to 1.9 by 6 mo; 3/6 showed growth response; no correlation between GH changes and height velocity.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Plasma GH response to GHRH-antagonist in morning vs evening
result Morning GH unchanged after antagonist infusion; evening GH decreased significantly (P<0.05, 75–135 min post-infusion), returning to baseline at 150 min. Other pituitary hormones unaffected.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH response (peak and AUC) to GHRH stimulation; basal IGF-I and BMI
result Amenorrheic patients had lower basal IGF-I and BMI but higher GHRH-induced GH peak and AUC vs controls; no correlation between BMI and IGF-I or LH.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH response to arginine, L-dopa, insulin hypoglycemia, clonidine, and pyridostigmine
result GHRH-Ant abolished GH response to exogenous GHRH and significantly suppressed GH responses to all 5 pharmacologic stimuli; endogenous GHRH is required for each.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH response to GHRH after FFA suppression with acipimox
result Obese GH peak 9.1 µg/L (GHRH alone) → 27.1 µg/L (single ACX) → 38.8 µg/L (1-month ACX); normal controls 23.5 µg/L (GHRH) and 58.5 µg/L (ACX+GHRH).
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested peak GH secretion rate (deconvolution analysis of serum GH by RIA)
result Hexarelin > GHRH alone (P<0.001); combination synergistic vs arithmetic sum (P=0.001); second hexarelin bolus at 120 min reduced peak GH vs first (P=0.03); synergism lost on repeated dosing.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Bioactivity/immunoactivity (B/I) ratio of GH measured by MTT-ESTA vs Hybritech IRMA after GHRH(1-29)-NH2 stimulation
result B/I ratios rose progressively toward GH peak concentrations then returned to ~1; enhanced bioactivity at peaks was labile at -20°C; attributed to GH isoforms undetectable by Hybritech IRMA.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested Height velocity, bone age progression, safety
result Height velocity increased from 4.1±0.9 cm/yr baseline to 8.0±1.5 at 6 mo and 7.2±1.3 cm/yr at 12 mo; 74% had good response at 6 months.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Peak GH response and IGF-I levels stratified by pituitary MRI morphology group
result Group I (stalk abnormality): peak GH median 2 mU/l (delayed 135-180 min). Group II (small AP/empty sella): median 34.8 mU/l. Group III (normal): median 30.8 mU/l, early peak but rapid decline.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested GH, prolactin, and cortisol release
result GHRH-(1-29)-NH2 1.0 µg/kg + low-dose hexarelin 0.125 µg/kg yielded massive GH release (115±32.8 mU/L), moderate PRL rise (84.9±27.5%), no cortisol rise; synergy confirmed.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested GH secretion, IGF-I, muscle strength, muscle bioenergetics (31P-NMRS), body composition (DEXA), metabolic markers
result Nocturnal GH release, AUPGH, and peak amplitude increased (P<.05); 2/6 strength measures improved; IGF-I, IGFBP-3, body composition, and metabolic markers unchanged.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested Height velocity (cm/year)
result 5/9 responders increased height velocity from 3.8 ± 0.7 to 8.0 ± 1.2 cm/year (p<0.05); 4 non-responders had higher peak GH to GHRH than responders.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Treatment studies
tested Height velocity, leg length SDS, bone age, skin-fold thickness, safety labs
result Height velocity increased significantly from 3.3 cm/yr to 6.0 cm/yr after 1yr GHRH (P=0.004); subsequent GH therapy yielded 7.5 cm/yr. Bone age advanced 1.1 yrs/chronological yr.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested peak serum GH at 0, 30, 60, 90, 120 min post-administration
result GHRH 1-29 i.v. evoked a GH rise in beta-thalassemia patients, but significantly lower than Hexarelin at 1 µg/kg (p<0.01); Hexarelin showed greater GH releasing capacity.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Peak serum GH, PRL, and cortisol concentrations under varying SS tone and at SS withdrawal
result SS infusion significantly reduced peak GH response to GHRH-(1-29)-NH2; hexarelin+GHRH synergistic with peak GH 52.6±7.2 mU/l despite SS50. SS withdrawal did not enhance GH response to GHRH alone.
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Peak GH increase over baseline and AUC after GHRP-6
result GHRH-Ant reduced peak GH response to GHRP-6 from 33.8±4.8 to 6.2±1.8 mcg/L (P<0.0001); AUC from 1701±278 to 376±113 mcg·min/L (P<0.001).
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Diagnostic & mechanistic studies
tested Serum GH response to GHRH-(1-29)-NH2 after pretreatment with CRH, ACTH, or hydrocortisone
result CRH pretreatment attenuated GH response (20.2→10.9 mU/l, P=0.01); ACTH augmented it (30.3 mU/l, P=0.01); hydrocortisone augmented it (36.4 mU/l, P=0.02).
Published human study (PubMed / Europe PMC), extracted from its abstract — not a CT.gov-registered trial.
Preclinical / mechanistic research
tested rat · Pharmacodynamic evaluation of a PEGylated analogue of human growth hormone releasing factor in rats and pigs.
result Preclinical publication captured from PubMed/Europe PMC; effect details require paper-level extraction.
Preclinical / mechanistic research
tested rat · Lack of effect of vasoactive intestinal peptide antagonists on blood flow in the rat thyroid. (PMID 1815206 · DOI 10.1016/0196-9781(91)90192-r)
result Preclinical publication captured from PubMed/Europe PMC; effect details require paper-level extraction.
Preclinical / mechanistic research
tested rat · A comparison of the biological activities of authentic rat GRF(1-43)OH with the analogue rat GRF(1-29)NH2.
result Preclinical publication captured from PubMed/Europe PMC; effect details require paper-level extraction.
Preclinical / mechanistic research
tested rat · An analogue of growth hormone releasing factor (GRF), (Ac-Try1, D-Phe2)-GRF-(1-29), specifically antagonizes the facilitation of the flexor reflex induced by intrathecal vasoactive intestinal peptide in rat spinal cord. (PMID 2067598 · DOI 10.1016/0143-4179(91)90104-q)
result Preclinical publication captured from PubMed/Europe PMC; effect details require paper-level extraction.
Preclinical / mechanistic research
tested rat · Blockade of growth hormone-releasing factor (GRF) activity in the pituitary and hypothalamus of the conscious rat with a peptidic GRF antagonist.
result Preclinical publication captured from PubMed/Europe PMC; effect details require paper-level extraction.
Preclinical / mechanistic research
tested rat · Interaction of growth hormone-releasing factor (GRF) and 14 GRF analogs with vasoactive intestinal peptide (VIP) receptors of rat pancreas. Discovery of (N-Ac-Tyr1,D-Phe2)-GRF(1-29)-NH2 as a VIP antagonist.
result Preclinical publication captured from PubMed/Europe PMC; effect details require paper-level extraction.
Preclinical / mechanistic research
tested rat · GH response to GRF (1-29) NH2 in female rats treated neonatally with estradiol benzoate or testosterone propionate. (PMID 2898557 · DOI 10.1016/0022-4731(88)90175-6)
result Preclinical publication captured from PubMed/Europe PMC; effect details require paper-level extraction.
Preclinical / mechanistic research
tested rat · Delayed release formulation of the somatostatin analog RC-160 inhibits the growth hormone (GH) response to GH-releasing factor-(1-29)NH2 and decreases elevated prolactin levels in rats.
result Preclinical publication captured from PubMed/Europe PMC; effect details require paper-level extraction.
Preclinical / mechanistic research
tested rat · Comparative structural requirements of thirty GRF analogs for interaction with GRF- and VIP receptors and coupling to adenylate cyclase in rat adenopituitary, liver and pancreas. (PMID 3018703 · DOI 10.1016/0196-9781(86)90164-6)
result Preclinical publication captured from PubMed/Europe PMC; effect details require paper-level extraction.
Preclinical / mechanistic research
tested rat · Decreased stimulation of adenylate cyclase by growth hormone-releasing factor in the anterior pituitary of old rats.
result Preclinical publication captured from PubMed/Europe PMC; effect details require paper-level extraction.
Preclinical / mechanistic research
tested rat · Histamine release on rat pleural and peritoneal mast cells elicited by human GRF(1-29)NH2.
result Preclinical publication captured from PubMed/Europe PMC; effect details require paper-level extraction.
Preclinical / mechanistic research
tested rat · Characterization of VIP receptor-effector system antagonists in rat and mouse peritoneal macrophages. (PMID 9085051 · DOI 10.1016/s0014-2999(96)00966-1)
result Preclinical publication captured from PubMed/Europe PMC; effect details require paper-level extraction.
Preclinical / mechanistic research
tested Interaction of the novel GH secretagogue hexarelin with GHRH in regulating the secretion of GH by cultured human pituitary somatotrophinomas in vitro.
result In-vitro publication captured from PubMed/Europe PMC; assay details require paper-level extraction.
Preclinical / mechanistic research
tested Interaction of carp growth hormone-releasing factor and somatostatin on in vitro release of growth hormone in rainbow trout (Oncorhynchus mykiss).
result In-vitro publication captured from PubMed/Europe PMC; assay details require paper-level extraction.
Preclinical / mechanistic research
tested Knocking down gene expression for growth hormone-releasing hormone inhibits proliferation of human cancer cell lines.
result In-vitro publication captured from PubMed/Europe PMC; assay details require paper-level extraction.
Preclinical / mechanistic research
tested Inhibition of estrogen receptor positive and negative breast cancer cell lines with a growth hormone-releasing hormone antagonist.
result In-vitro publication captured from PubMed/Europe PMC; assay details require paper-level extraction.
Preclinical / mechanistic research
tested Stimulatory effect of growth hormone-releasing hormone (GHRH(1-29)NH2) on the proliferation, VEGF and chromogranin A secretion by human neuroendocrine tumor cell line NCI-H727 in vitro.
result In-vitro publication captured from PubMed/Europe PMC; assay details require paper-level extraction.
Preclinical / mechanistic research
tested In vitro responses of rainbow trout (Oncorhynchus mykiss) somatotrophs to carp growth hormone-releasing factor (GRF) and somatostatin. (PMID 1981568 · DOI 10.1016/0016-6480(90)90173-j)
result In-vitro publication captured from PubMed/Europe PMC; assay details require paper-level extraction.
Preclinical / mechanistic research
tested The novel VIP-like hypothalamic polypeptide PACAP interacts with high affinity receptors in the human neuroblastoma cell line NB-OK. (PMID 2172943 · DOI 10.1016/0196-9781(90)90194-a)
result In-vitro publication captured from PubMed/Europe PMC; assay details require paper-level extraction.
Preclinical / mechanistic research
tested The effect of GHRH on TSH release in rats in vivo and in vitro.
result In-vitro publication captured from PubMed/Europe PMC; assay details require paper-level extraction.
Preclinical / mechanistic research
tested Subcellular distribution of proteolytic activities degrading bioactive peptides and analogues in the rat small intestinal and colonic enterocytes.
result In-vitro publication captured from PubMed/Europe PMC; assay details require paper-level extraction.