The effects of antagonists of vasoactive intestinal peptide on nonadrenergic noncholinergic inhibitory responses in feline airways.
Thompson. D C DC; Altiere. R J RJ; Diamond. L L
Key Findings
- GRF‑1‑29 failed to antagonize VIP‑induced relaxation in feline intrapulmonary bronchi.
- A second VIP antagonist only reduced responses at the highest VIP concentrations.
- Both antagonists are ineffective as competitive VIP blockers in cat airway tissue.
Practical Outcomes
- For biohackers or self‑experimenters, this study offers no actionable protocol or health benefit. It simply shows that GRF‑1‑29 and similar VIP antagonists are not useful for modulating airway function in humans, so they should not be pursued for respiratory or performance‑related applications.
Summary
In a cat lung study, the peptide GRF‑1‑29 (used as a VIP blocker) didn’t stop the airway‑relaxing effects of VIP, and another VIP blocker only worked at very high doses. This means these compounds aren’t reliable tools for influencing VIP‑driven airway responses.
Abstract
Relaxations of the feline intrapulmonary bronchus (IPB) induced by VIP or nonadrenergic noncholinergic (NANC) inhibitory nervous stimulation were unaffected by the VIP receptor antagonist [Ac-Tyr1,D-Phe2]-GRF (1-29) (30 microM). A second VIP antagonist, [pCl-D-Phe6,Leu17]-VIP (30 microM), also had no effect on NANC relaxation responses or IPB sensitivity to VIP. However, responses to three of the four highest VIP concentrations were inhibited by this antagonist. These results indicate that [Ac-Tyr1,D-Phe2]-GRF (1-29) and [pCl-D-Phe6,Leu17]-VIP are not effective competitive antagonists of VIP receptors in feline airways and, hence, have but limited applicability in determining the role of VIP in mediating airway NANC inhibitory responses in this tissue.
Study Information
pubmed
1988
1988-03-01T00:00:00.000Z
10.1016/0196-9781(88)90284-7
23
8