“Last year, Huston’s team showed that vagus nerve stimulation activates a type of immune cell, called T cells, in the spleen, the organ that helps filter germs and old cells out of blood. These T cells then activate platelets in the spleen; platelets are the cell fragments that set off blood clot formation.

Upon re-entering circulation, the primed platelets are better able to respond to injury-related cues. In mice with hemophilia, a disorder in which blood can’t clot properly, nerve stimulation reduced bleeding, the team found.

To test whether the same mechanism existed in humans, Huston’s team collaborated with the Dallas-based biomedical company Five Liters to recruit healthy volunteers. They used an approved device to zap the auricular branch of vagus nerve, which runs behind the ear, for 30 minutes in each person. They collected blood samples before and after the treatment.

Following vagus nerve stimulation, the volunteers’ blood contained higher levels of markers of blood platelet activation.

These results, presented in October at the Society for Neuroscience conference in Chicago, showed for the first time ‘that there is a neural tourniquet pathway in humans,’ Huston said. ‘And it appears that we can activate this neural tourniquet pathway non-invasively.'”

From Live Science.