Distribution of Substance P and Calcitonin Gene-related Peptide-like lmmunoreactive Nerve Fibers in the Rat Temporomandibular Joint

Abstract

The density and distribution of substance P-like immunoreactive (SP-LI) and calcitonin gene-related peptide-like immunoreactive (CGRP-LI) nerve fibers in rat temporomandibular joint (TMJ) were investigated in whole-mount preparations and frozen sections by immunohistochemistry with the avidin-biotin-peroxidase complex method. Both types of immunoreactive nerves were observed primarily in the joint capsule, the peripheral articular disc, the synovial membrane, and the periosteum. The distribution of CGRP-LI nerves was similar to that of SP-LI nerves. The anterior portion of the joint capsule and disc was most densely innervated, followed by the posterior, lateral, and medial portions. In addition, CGRP-LI nerves were more numerous and more dense in immuno-intensity than SP-LI nerves. In the synovial membrane, many SP- and CGRP-LI nerves terminated in the subsynovial layer, but some branches extended into the superficial synovial lining layer close to the joint cavity. Immunolabeled nerves were prominently located in the disc attachment and peripheral portion of the disc, and occasional nerves were located in the dense collagenous disc band as an actual disc. However, no fibers were detected in the central disc band. Thus, most of the disc was not innervated by any nerves. The present study provides a morphological basis for the possible roles of neuropeptides in endocytosis by synoviocytes, regulation of blood flow in the synovial membrane, nociception mechanisms of the TMJ, and modulation of the inflammatory response in the TMJ.

Pathogenesis of Degenerative Joint Disease in the Human Temporomandibular Joint

“…This discovery suggests an important biological role for these neuropeptides in peripheral tissues. Nerve terminals containing these proinflammatory neuropeptides (i.e., SP and CGRP) have been detected in various tissues of the temporomandibular joint complex Ichikawa et al, 1989Ichikawa et al, , 1990Appelgren, 1991Appelgren, , 1993aHolmlund et al, 1991;Kido et al, 1993). The highest density of these neurons is found in the anterior aspect of the capsular ligament and in the retrodiscal tissue (Johansson etal, 1986;Kidoetal, 1993).…”

Sex Differences in Brainstem Neural Activation after Injury to the TMJ Region

“…The TMJ region is innervated by a complex network of fibers originating from trigeminal, upper cervical spinal, and vagal sensory ganglion neurons [Klineberg, 1971;Denny-Brown and Yanagisawa, 1973;Widenfalk and Wiberg, 1990;Kido et al, 1993;Uddman et al, 1998]. The widespread overlap of peripheral fields and central projection from these sensory neurons likely contributes to the poor localization of TMD pain.…”

Anatomical study of the human discomallear ligament using cone beam computed tomography imaging and morphological observations

“…In our study, anti-SP-, PGP-, and CGRP-positive fibers were also found in the posterior region of the TMJ disc. Previous reports have indicated that anti-SP- and CGRP-positive fibers were found in the attachment of the lateral pterygoid muscle to the TMJ disc (Johansson, 1986;Ichikawa, 1989, Kido, 1993, Shimizu, 1996. The specific location of the markers is related to the function of the sensory receptor of control for excess jaw movements or tension of the TMJ disc.…”

“…SP-and CGRP-positive nerve fibers exist at the attachment of the lateral pterygoid muscle and the TMJ disc (Johansson, 1986;Ichikawa, 1989, Kido, 1993, Shimizu, 1996, and the distribution of these markers differ in the TMJ disc (Tahmasebi- Sarvestani, 1997Sarvestani, , 2001). Previous reports have described the vasculature and nerve structures of the side of the lateral pterygoid muscle (Griffin and Shape, 1960;Castelli, 1963;Sarnat and Engel, 1951;Parsons and Boucher, 1966).…”