Protein gene-product 9.5 in developing mouse circumvallate papilla: comparison with neuron-specific enolase and calcitonin gene-related peptide.
The present study was made to investigate the ontogeny of protein gene-product 9.5 (PGP 9.5)-like immunoreactivity (-LI) in the developing mouse circumvallate papilla (CVP), and its distribution was compared to that of neuron-specific enolase (NSE) and calcitonin gene-related peptide (CGRP). In adult CVP, PGP 9.5-LI was observed in the subgemmal nerve plexus; some thin PGP 9.5-like immunoreactive (-IR) nerve fibers penetrated taste buds and apical epithelium. PGP 9.5-LI was also observed in the spindle-shaped cells in taste buds, and a small number of round- or oval-shaped ganglionic cells in the lamina propria. The distribution of NSE-LI was comparable to that of PGP 9.5-LI. CGRP-LI was observed in the nerve fibers only; distribution of CGRP-IR nerve fibers was similar to that of PGP 9.5-IR nerve fibers, although the number of CGRP-IR nerve fibers was smaller than that of PGP 9.5-IR nerve fibers. At least six developmental stages were defined with regard to the developmental changes in the distribution of PGP 9.5-LI from embryonic day (E) 12 to adulthood: Stage I (E12-13)-a dense nerve plexus of PGP 9.5-IR nerve fibers was detected in the lamina propria beneath the core of newly-formed papilla. Stage II (E14-16) - thin PGP 9.5-IR nerve fibers penetrated the apical epithelium, and a few round-shaped cells in the apical epithelium also displayed PGP 9.5-LI. Stage III (E17-18) - thin PGP 9.5-IR nerve fibers penetrated the inner lateral epithelium of the trench. Stage IV [Postnatal day (P) 0-3] - many PGP 9.5-IR nerve fibers penetrated the outer lateral epithelium of the trench; later in this stage, taste buds appeared. Stage V (P5-10) - a small number of PGP 9.5-IR cells in the taste buds appeared, and their number increased gradually. Stage VI (P14-adult) - the number of PGP 9.5-IR taste cells increased and reached the adult level, while the number of PGP 9.5-IR nerve fibers decreased. The development of NSE-LI was similar to that of PGP 9.5-LI. CGRP-IR nerve fibers were detected at E12 in the lamina propria, and the development of the intraepithelial CGRP-IR nerve fibers was similar to that of PGP 9.5-IR nerve fibers. The present results indicate that invasion by nerve fibers of the epithelium of lingual papillae occurs in a complex manner, and that these nerve fibers may participate in the formation of the taste buds.
Wakisaka
S
S
Department of Oral Anatomy and Developmental Biology, Osaka University Faculty of Dentistry, Japan. wakisaka@dent.osaka-u.ac.jp
Miyawaki
Y
Y
Youn
S H
SH
Kato
J
J
Kurisu
K
K
D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism*; D019084:Fluorescent Antibody Technique, Indirect; D007150:Immunohistochemistry; D051379:Mice; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D010751:Phosphopyruvate Hydratase / Q000378:metabolism*; D013650:Taste Buds / Q000033:anatomy & histology / Q000737:chemistry* / Q000196:embryology / Q000254:growth & development; D013869:Thiolester Hydrolases / Q000378:metabolism*; D014059:Tongue / Q000737:chemistry / Q000196:embryology* / Q000254:growth & development* / Q000294:innervation; D043222:Ubiquitin Thiolesterase
D009419:Nerve Tissue Proteins; D013869:Thiolester Hydrolases; D043222:Ubiquitin Thiolesterase; D010751:Phosphopyruvate Hydratase; D015740:Calcitonin Gene-Related Peptide