Oral GHRP-2 Successfully Releases Growth Hormone in Young Goats

Oral administration of GHRP-2 at 5-10 mg/kg stimulated significant GH release in 1-month-old goats but not 3-month-old goats, demonstrating oral peptide bioactivity varies with age in large animals.

Hashizume, T et al.·Domestic animal endocrinology·1999·Preliminary EvidenceAnimal StudyAnimal Study
RPEP-00526Animal StudyPreliminary Evidence1999RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Animal Study
Evidence
Preliminary Evidence
Sample
Not reported

What This Study Found

Oral GHRP-2 (5-10 mg/kg) stimulated significant GH release in 1-month-old goats (peak at 15 min) but not in 3-month-old goats, demonstrating age-dependent oral peptide bioavailability in ruminants.

Key Numbers

How They Did This

Animal study in goats. GHRP-2 dissolved in saline was administered orally twice at 2-hour intervals to 1-month and 3-month-old goats (n=5-6 per group). Plasma GH levels were measured over time.

Why This Research Matters

Demonstrating oral peptide activity in large animals is important for both agricultural applications (promoting growth) and for understanding oral peptide delivery across species. The age-dependent absorption highlights gut maturation as a factor.

The Bigger Picture

Oral peptide delivery remains a major pharmaceutical challenge. This study shows it's achievable in young animals where gut permeability is higher, supporting research into formulations that might enable oral peptide therapy in humans.

What This Study Doesn't Tell Us

Ruminant digestive system differs significantly from human. Age-dependent response may reflect gut development specific to goats. Relatively high doses required (5-10 mg/kg). Not directly translatable to human oral delivery.

Questions This Raises

  • ?Why does oral peptide absorption decline with age?
  • ?Could gut permeability enhancers enable oral GHRP-2 in older animals?
  • ?Does this age-dependent absorption apply to human infants vs adults?

Trust & Context

Key Stat:
15-minute oral response Oral GHRP-2 elevated plasma GH within 15 minutes in young goats, demonstrating rapid oral peptide absorption is possible
Evidence Grade:
Preliminary animal evidence in a non-standard model (goats), demonstrating proof-of-concept for oral peptide activity but with limited translatability to humans.
Study Age:
Published in 1999. Oral peptide delivery research has advanced significantly with new formulation technologies.
Original Title:
Oral administration of peptidergic growth hormone (GH) secretagogue KP102 stimulates GH release in goats.
Published In:
Domestic animal endocrinology, 16(1), 31-9 (1999)
Database ID:
RPEP-00526

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / Observational
Case Report / Animal StudyOne case or non-human subjects
This study

Tests effects in animals (usually mice or rats), not humans.

What do these levels mean? →

Frequently Asked Questions

Can GH peptides work when taken by mouth?

This study shows oral GHRP-2 works in young goats, demonstrating it can survive digestion and reach the bloodstream. However, the doses required were high, and absorption declined with age as the gut matured.

Why did it work in young but not older goats?

Young animals have more permeable intestinal lining, allowing larger molecules like peptides to be absorbed. As the gut matures, permeability decreases, making oral peptide delivery more challenging — a key barrier for human peptide drugs.

Read More on RethinkPeptides

Cite This Study

RPEP-00526·https://rethinkpeptides.com/research/RPEP-00526

APA

Hashizume, T; Kawai, M; Ohtsuki, K; Ishii, A; Numata, M. (1999). Oral administration of peptidergic growth hormone (GH) secretagogue KP102 stimulates GH release in goats.. Domestic animal endocrinology, 16(1), 31-9.

MLA

Hashizume, T, et al. "Oral administration of peptidergic growth hormone (GH) secretagogue KP102 stimulates GH release in goats.." Domestic animal endocrinology, 1999.

RethinkPeptides

RethinkPeptides Research Database. "Oral administration of peptidergic growth hormone (GH) secre..." RPEP-00526. Retrieved from https://rethinkpeptides.com/research/hashizume-1999-oral-administration-of-peptidergic

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkPeptides research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.