HTR3A and irritable bowel syndrome: One study demonstrated that EA stimulation on ST36 and ST37 could reduce AWR scores as well as the mRNA and protein expressions of Epac1, Piezo2, 5-HT3, and 5-HT3 receptors in distal colonic tissue, which was better than the IBS group and the sham EA group (Guo et al., 2022).