title: Effect of Brn-3a deficiency on parvalbumin-, calbindin D-28k-, calretinin- and calcitonin gene-related peptide-immunoreactive primary sensory neurons in the trigeminal ganglion.
abstract: Immunohistochemistry for parvalbumin, calbindin D-28k, calretinin and calcitonin gene-related peptide (CGRP) was performed on the trigeminal ganglion and oro-facial tissues in Brn-3a wildtype and knockout mice at embryonic day 18.5 and postnatal day 0. In wildtype mice, the trigeminal ganglion contained abundant parvalbumin-, calbindin D-28k- and CGRP-immunoreactive neurons while the ganglion was almost devoid of calretinin-immunoreactive neurons. In Brn-3a knockout mice, a 63% decrease of parvalbumin-immunoreactive neurons was detected. In contrast, the absence of Brn-3a dramatically increased the number of calbindin D-28k-immunoreactive (3.5-fold increase) and calretinin-immunoreactive neurons (91-fold increase). The number of CGRP-immunoreactive neurons, however, was not altered by the Brn-3a deficiency. Cell size analysis indicated that loss of Brn-3a increased the proportions of small (<100 microm (2)) parvalbumin-, calbindin D-28k- and CGRP-immunoreactive neurons while it decreased those of large (>200 microm(2)) immunoreactive cells. Calretinin-immunoreactive neurons were either small or medium (100-200 microm (2)) in mutant mice. The oro-facial tissues contained parvalbumin-, calbindin D-28k- and CGRP-immunoreactive fibers, but not calretinin-immunoreactive ones in wildtype mice. In Brn-3a knockout mice, the number of parvalbumin-immunoreactive fibers markedly decreased in the infraorbital nerve and parvalbumin-immunoreactive endings disappeared in the vibrissa. In contrast, the number of calbindin D-28k-immunoreactive fibers increased significantly in the infraorbital and mental nerves. In addition, calbindin D-28k-immunoreactive endings appeared in the vibrissa. As well, some fibers showed calretinin-immunoreactivity in the infraorbital nerve of the mutant. However, no obvious change of CGRP-immunoreactive fibers was observed in the oro-facial region of knockout mice. Taken together, our data suggest that Brn-3a deficiency has effects on the expression of neurochemical substances in the trigeminal ganglion.
authors.affiliation: Department of Oral Function and Anatomy, Okayama University Graduate School of Medicine and Dentistry, 2-5-1 Shikata-cho, Okayama 700-8525, Japan. hiroichi@md.okayama-u.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Ichikawa
authors.forename: T
authors.initials: T
authors.lastname: Yamaai
authors.forename: D M
authors.initials: DM
authors.lastname: Jacobowitz
authors.forename: Z
authors.initials: Z
authors.lastname: Mo
authors.forename: M
authors.initials: M
authors.lastname: Xiang
authors.forename: T
authors.initials: T
authors.lastname: Sugimoto
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D064032:Calbindin 2; D064026:Calbindins; D015740:Calcitonin Gene-Related Peptide / Q000032:analysis* / Q000276:immunology; D004268:DNA-Binding Proteins / Q000172:deficiency* / Q000235:genetics; D005145:Face / Q000294:innervation; D007150:Immunohistochemistry; D051379:Mice; D018345:Mice, Knockout; D009412:Nerve Fibers / Q000737:chemistry / Q000378:metabolism; D009475:Neurons, Afferent / Q000737:chemistry / Q000378:metabolism*; D010320:Parvalbumins / Q000032:analysis* / Q000276:immunology; D064030:S100 Calcium Binding Protein G / Q000032:analysis* / Q000276:immunology; D050818:Transcription Factor Brn-3; D050819:Transcription Factor Brn-3A; D014157:Transcription Factors / Q000172:deficiency* / Q000235:genetics; D012668:Trigeminal Ganglion / Q000737:chemistry / Q000196:embryology / Q000378:metabolism*; D014738:Vibrissae / Q000294:innervation
chemical_list: C576511:Calb2 protein, mouse; D064032:Calbindin 2; D064026:Calbindins; D004268:DNA-Binding Proteins; D010320:Parvalbumins; C494189:Pou4f1 protein, mouse; D064030:S100 Calcium Binding Protein G; D050818:Transcription Factor Brn-3; D050819:Transcription Factor Brn-3A; D014157:Transcription Factors; D015740:Calcitonin Gene-Related Peptide