The orally administered GH secretagogue CP-424,391 reduced infarct size by ~50% after ischemia-reperfusion in rabbits, demonstrating that oral GH peptide drugs can provide significant cardioprotection.
~50% less damageAn oral GH secretagogue halved myocardial infarct size in rabbits — proof that a pill could protect against heart attack damage
What the researchers found
Oral CP-424,391 (25 mg/kg/day for 7 days) reduced myocardial infarct size by ~50% in an in-vivo rabbit ischemia-reperfusion model, demonstrating significant cardioprotection from an orally available GH secretagogue.
Why it matters
An oral pill that halves heart attack damage would be a major medical advance. This proof-of-concept shows GH secretagogues can achieve this through their cardiac receptor (independent of GH release).
How the study worked
Animal study in rabbits. CP-424,391 administered orally for 7 days before ischemia-reperfusion. Infarct size measured by TTC staining as percentage of area at risk.
What this study cannot tell us
Rabbit model. Pre-treatment design (7 days before ischemia) — clinical application would require chronic preventive use. The specific mechanism (cardiac GHS-R vs systemic effects) was not dissected.
How to read the evidence
Moderate evidence from an in-vivo ischemia-reperfusion model with quantitative infarct size measurement, limited to a single animal species.
When this study was published
Published in 2001. Cardiac GH secretagogue research has continued, though no cardioprotective GH secretagogue has reached clinical approval yet.
The bigger picture
Heart attacks are the leading cause of death worldwide. An oral preventive medication that significantly reduces cardiac damage could save millions of lives, and GH secretagogues now have proof-of-concept for this application.
Questions still open
- Could oral GH secretagogues be given to heart attack patients in the ER?
- Does the protection require chronic pretreatment or can it work acutely?
- Would this protect the human heart similarly?
Common questions
Can a pill protect the heart from a heart attack?
How does a GH peptide protect the heart?
Read the original research
Efficacy of a growth hormone-releasing peptide mimetic in cardiac ischemia/reperfusion injury.
European journal of pharmacology, 432(2-3), 195-202
Citation
MacAndrew, J T; Ellery, S S; Parry, M A; Pan, L C; Black, S C. (2001). Efficacy of a growth hormone-releasing peptide mimetic in cardiac ischemia/reperfusion injury.. European journal of pharmacology, 432(2-3), 195-202.