Specific labelling by [125I]helodermin of high-affinity VIP receptors in rat liver membranes.
Robberecht. P P; Waelbroeck. M M; de Neef. P P; Camus. J C JC; Vandermeers. A A; Vandermeers-Piret. M C MC; Christophe. J J
Key Findings
- Helodermin binds rapidly and reversibly to high‑affinity VIP receptors in rat liver membranes
- Binding is displaced by GTP, indicating a G‑protein‑linked receptor
- VIP has the highest affinity, followed by helodermin, secretin, and hpGRF(1‑29)-NH2
Practical Outcomes
- The main takeaway is that helodermin (and similar VIP‑like peptides) can engage VIP receptors, which are involved in many metabolic and vascular processes. However, the research is purely mechanistic in rats and offers no actionable dosing, safety, or efficacy guidance for human use, so it isn’t directly useful for current biohacking protocols.
Summary
This study shows that a venom peptide called helodermin can stick to the same receptors in rat liver that the body’s natural VIP hormone uses, and that this binding can trigger a cellular signal (cAMP). It’s a basic lab experiment, not a human trial, and doesn’t give any dosing or safety info for people.
Abstract
Helodermin, a newly isolated peptide from Gila Monster venom, is structurally related to VIP and secretin. When used as radioligand, [125I]helodermin bound rapidly and reversibly to crude rat liver membranes, the dissociation being accelerated by GTP. Competition binding curves of [125I]helodermin and [125I]VIP with unlabelled peptides showed the following order of decreasing affinity: VIP greater than helodermin greater than secretin greater than hpGRF(1-29)-NH2. The shape of binding curves and of concurrent adenylate cyclase activation is compatible with the specific labelling, by [125I]helodermin, of a class of high-affinity VIP receptors that is capable to stimulate adenylate cyclase.
Study Information
pubmed
1984
1984-06-25T00:00:00.000Z
10.1016/0014-5793(84)80872-8
45
13