Oral GHRP-2 successfully stimulated GH release in adult goats, with absorption occurring in the intestines after bypassing the rumen, demonstrating oral peptide viability in large adult animals.
Intestinal absorptionGHRP-2 works orally in adult goats by surviving to the intestines for absorption — the rumen alone can't absorb it
What the researchers found
Oral GHRP-2 stimulated GH release in adult goats when absorbed through the intestines (not rumen), demonstrating post-gastric oral peptide bioactivity in adult large animals with mature digestive systems.
Why it matters
Oral peptide delivery is the holy grail of peptide therapeutics. Showing it works in adult goats with complex digestive systems brings oral peptide drugs closer to practical reality.
How the study worked
Animal study in adult goats. GHRP-2 administered orally, directly into the rumen, or into the intestines via fistulae. Plasma GH measured after each route to determine absorption site.
What this study cannot tell us
Goat ruminant digestive system differs from human. High doses still required. Oral bioavailability as a percentage was not precisely quantified.
How to read the evidence
Preliminary animal evidence with clever route-of-absorption experiments in adult large animals, though limited in translatability to humans.
When this study was published
Published in 2001. Oral peptide delivery technology has advanced significantly, with enteric-coated and absorption-enhanced peptide formulations now in clinical development.
The bigger picture
The barrier to oral peptide therapy is digestive destruction. This study shows peptides can survive transit through the stomach and be absorbed in the intestine, even in adult animals — supporting the development of oral peptide drugs for humans.
Questions still open
- Can enteric coating protect peptides through the stomach for intestinal absorption?
- What fraction of oral GHRP-2 reaches the intestinal absorption site intact?
- Does this translate to human oral peptide delivery?
Common questions
Can peptide drugs work when swallowed?
How does this help humans?
Read the original research
Plasma growth hormone (GH) responses after administration of the peptidergic GH secretagogue KP102 into the oral cavity, rumen, abomasum and duodenum in adult goats.
Domestic animal endocrinology, 20(1), 37-46
Citation
Hashizume, T; Tanabe, Y; Ohtsuki, K; Mori, A; Matsumoto, N; Hara, S. (2001). Plasma growth hormone (GH) responses after administration of the peptidergic GH secretagogue KP102 into the oral cavity, rumen, abomasum and duodenum in adult goats.. Domestic animal endocrinology, 20(1), 37-46.