NK1, NK2, NK3 and CGRP1 receptors identified in rat oral soft tissues, and in bone and dental hard tissue cells

• Published in: Cell and tissue research Vol. 311; no. 3; pp. 383 - 391
• Main Authors: Fristad, I, Vandevska-Radunovic, V, Fjeld, K, Wimalawansa, S J, Hals Kvinnsland, I
• Format: Journal Article
• Language: English
• Published: Germany Springer Nature B.V 01.03.2003
• Subjects: Animals; Blood Vessels - cytology; Blood Vessels - innervation; Blood Vessels - metabolism; Epithelial Cells - cytology; Epithelial Cells - metabolism; Female; Fibroblasts - cytology; Fibroblasts - metabolism; Gingiva - cytology; Gingiva - innervation; Gingiva - metabolism; Immunohistochemistry; Jaw - cytology; Jaw - innervation; Jaw - metabolism; Mouth Mucosa - cytology; Mouth Mucosa - innervation; Mouth Mucosa - metabolism; Neuropeptides - metabolism; Rats; Rats, Wistar; Receptors, Calcitonin Gene-Related Peptide - metabolism; Receptors, Neurokinin-1 - metabolism; Sensory Receptor Cells - cytology; Sensory Receptor Cells - metabolism; Tooth - cytology; Tooth - innervation; Tooth - metabolism
• DOI: 10.1007/s00441-002-0691-z
• ISSN: 0302-766X

The distribution of the tachykinin receptors neurokinin-1 (NK1), neurokinin-2 (NK2) and neurokinin-3 (NK3), and the calcitonin gene-related peptide-1 (CGRP1) receptor were examined in rat teeth and tooth-supporting tissues by immunohistochemical methods and light and confocal microscopy. Western blot analysis was performed to identify the NK1- and the CGRP1-receptor proteins in the dental pulp. The results showed that odontoblasts and ameloblasts, cementoblasts and cementocytes, osteoblasts and osteocytes are all supported with the tachykinin receptors NK1 and NK2, but a distinct, graded cellular labeling pattern was demonstrated. The ameloblasts were also positive for CGRP1 receptor. Blood vessels in oral tissues expressed the tachykinin receptors NK1, NK2 and NK3, and the CGRP1 receptor. Both gingival and Malassez epithelium were abundantly supplied by NK2 receptor. Pulpal and periodontal fibroblasts demonstrated NK1 and NK2 receptors. Western blot analysis identified both the NK1- and the CGRP1-receptor proteins in the dental pulp. These results clearly indicate that the neuropeptides substance P, neurokinin A, neurokinin B and CGRP, released from sensory axons upon stimulation, directly modulate the function of the different types of bone and dental hard tissue cells, and regulate functions of blood vessels, fibroblasts and epithelial cells in oral tissues.