Capsaicin + TRPV1
Caterina MJ, Schumacher MA, Tominaga M, Rosen TA, Levine JD, Julius D. The capsaicin receptor: a heat-activated ion channel in the pain pathway. Nature. 1997;389(6653):816–824. doi:10.1038/39807 · PubMed 9349813
A team at the University of California, San Francisco set out to find the receptor that capsaicin — the compound that makes chili peppers hot — acts on. Working with genetic material from sensory nerve cells, they isolated the gene for that receptor and tested how it behaved in cells in the lab.
The capsaicin receptor turned out to be an ion channel in pain-sensing nerves, related to the TRP family of channels. The same channel also opened in response to temperatures in the painfully hot range — which is why chili registers as “heat” and not just as a flavor. The paper called the receptor VR1; it is now known as TRPV1.
This was not a clinical trial of Allicore. It was molecular and cell-level lab work: nobody in this study swallowed cayenne or any supplement. It explains how capsaicin produces the sensation of heat. It identifies a heat-and-pain sensor, and says nothing about circulation, metabolism, or any benefit from eating cayenne.