Bagues, AnaMartín-Fontelles, Mª IsabelEsteban-Hernández, JesúsSánchez-Robles, Eva Mª2024-07-262024-07-262017Bagüés A, Martín-Fontelles MI, Esteban-Hernández J, Sánchez-Robles EM. Characterization of the nociceptive effect of carrageenan: Masseter versus gastrocnemius. Muscle Nerve. 2017 Oct;56(4):804-813.https://hdl.handle.net/10115/38878Introduction: To better understand the pathophysiology of chronic muscle pain, there are multiple animal models that mimic different acute/chronic pain conditions, such as carrageenan injection. Our previous studies demonstrated differences between muscles of different innervation in acute pain. In this study we characterized the effect of carrageenan in 2 muscles: masseter (trigeminal innervation) and gastrocnemius (spinal innervation). Methods: Carrageenan (3%, 6%, and 9%) was injected into the masseter and gastrocnemius of rats. Mechanical, heat, and chemical nociceptive thresholds were measured for 14 days. Results: Carrageenan did not induce mechanical allodynia or thermal hypersensitivity in either muscle. Instead, it induced a short-lasting mechanical hyperalgesia, greater in the masseter than in the gastrocnemius. Conclusion: Carrageenan injected into the masseter and gastrocnemius induces a short-lasting hyperalgesia. These results could indicate a higher susceptibility of orofacial muscles to this type of insult and, consequently, a difference between trigeminal and spinal innervation. Muscle Nerve 56: 804-813, 2017.carrageenan; gastrocnemius; masseter; muscle pain; rat.info:eu-repo/semantics/article10.1002/mus.25538info:eu-repo/semantics/closedAccess