Transverse acupuncture reduced menstrual pain in rats by suppressing immune-cell inflammation driven by the eotaxin and chemokine receptor pathway.
Researchers induced cold-related menstrual pain in rats, then compared perpendicular and transverse acupuncture at a lower-leg acupoint. Some animals received a substance that activates the chemokine receptor pathway before treatment. They assessed pain behaviours, uterine contractions, inflammatory molecules, receptor expression, and uterine immune-cell activity using physiological recordings, tissue staining, molecular analysis, and protein measurements.
Acupuncture reduced pain and excessive uterine contractions, with transverse needling producing the strongest effects. Transverse needling lowered inflammatory signalling, reduced recruitment and activation of eosinophils and mast cells, and decreased histamine-related responses in uterine tissue. Activating the chemokine receptor pathway prevented these benefits, indicating that suppression of this inflammatory pathway underlies the observed pain relief.
