또한 귀에 침 자극을 가하면 베타엔도르핀을 비롯한 오피오이드 펩티드가 분비돼 통증을 억제한다고 알려졌다.
It is also known that when acupuncture stimulation is applied to the ear, opioid peptides, including beta-endorphin, are secreted to suppress pain.