Brn-3a deficiency increases tyrosine hydroxylase-immunoreactive neurons in the dorsal root ganglion.
Immunohistochemistry for tyrosine hydroxylase (TH) was performed on the dorsal root ganglia (DRG) in wild-type, heterozygous and Brn-3a knockout mice at embryonic day 18.5. TH-immunoreactive (-IR) neurons were detected in the DRG of wild-type and heterozygous mice, but their proportion was greatly increased by the loss of Brn-3a function (wild-type and heterozygot, 8.4%; knockout, 20.9%). IR neurons were of various sizes in wild-type (mean+/-S.D.=118.1+/-55.4 microm2, range=26.6-306.3 microm2) and heterozygous mice. In the knockout mice, however, TH-IR neurons were mostly small (mean+/-S.D.=68.2+/-34.3 microm2, range=11.8-166.8 microm2). The present study suggests that Brn-3a may normally suppress TH expression in many small DRG neurons but activate TH expression in large DRG neurons.
Ichikawa
Hiroyuki
H
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
Mo
Zeqian
Z
Xiang
Mengqing
M
Sugimoto
Tomosada
T
D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism; D002395:Catecholamines / Q000096:biosynthesis; D048429:Cell Size; D004268:DNA-Binding Proteins / Q000235:genetics*; D005727:Ganglia, Spinal / Q000166:cytology / Q000378:metabolism*; D006579:Heterozygote; D006720:Homozygote; D051379:Mice; D018345:Mice, Knockout; D009475:Neurons, Afferent / Q000166:cytology / Q000378:metabolism*; D009619:Nociceptors / Q000502:physiology; D010146:Pain / Q000378:metabolism; D050818:Transcription Factor Brn-3; D050819:Transcription Factor Brn-3A; D014157:Transcription Factors / Q000235:genetics*; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism*; D015854:Up-Regulation / Q000502:physiology*
D002395:Catecholamines; D004268:DNA-Binding Proteins; C494189:Pou4f1 protein, mouse; D050818:Transcription Factor Brn-3; D050819:Transcription Factor Brn-3A; D014157:Transcription Factors; D014446:Tyrosine 3-Monooxygenase; D015740:Calcitonin Gene-Related Peptide