Associating high intensity and modulated frequency of TENS delays analgesic tolerance in rats

• Published in: European journal of pain 2015-03, Vol.19 (3), p.369-376
• Main Authors: Lima, L.V., Cruz, K.M.L., Abner, T.S.S., Mota, C.M.D., Agripino, M.E.J., Santana-Filho, V.J., DeSantana, J.M.
• Format: Article
• Language: English
• Subjects: Animals; Arthralgia - etiology; Arthralgia - therapy; Arthritis, Experimental - complications; Disease Models, Animal; Hyperalgesia - therapy; Male; Pain Threshold - physiology; Rats; Rats, Wistar; Transcutaneous Electric Nerve Stimulation
• ISSN: 1090-3801; 1532-2149
• DOI: 10.1002/ejp.555

Background Transcutaneous electrical nerve stimulation (TENS) is a non‐invasive analgesic resource extensively used in painful conditions. However, preclinical studies suggest that the prolonged use of TENS results in the development of tolerance to its analgesic effect. The present study investigated the analgesic effect and development of tolerance to TENS with four different stimulation protocols. Methods Male Wistar rats induced with joint inflammation were divided into four groups: sensory intensity, low motor intensity, high motor intensity and sham groups. TENS was applied daily for 20 min with alternating frequency between 4 and 100 Hz until tolerance development was evidenced. Mechanical hyperalgesia was measured before and after each TENS daily application. Results After TENS, tolerance was evidenced There was a significant reduction in the mechanical withdrawal threshold in all groups 24 h after induction of inflammation (p