Substance P expression in TRPV1 and trkA-positive dorsal root ganglion neurons innervating the mouse lung.
In the present study, the co-localisation of substance P (SP) with the vanilloid receptor TRPV1 and the neurotrophin receptor tyrosine kinase trkA was analysed in airway-specific murine dorsal root ganglion (DRG) neurons. DRG neurons labelled with Fast Blue were predominantly found at the segmental levels T2-T5. Immunoreactivity for the receptor TRPV1 was localized to 12% of Fast Blue labelled DRG neurons. Double-labelling immunohistochemistry revealed that a substantial number of them also co-express SP (7.6 +/- 1.1% (mean +/- S.E.M.)), whereas neurons with immunoreactivity for TRPV1 only were found in 4.4 +/- 1.3% of the retrogradely labelled neuronal population. Further analysis of retrogradely labelled neurons showed that their majority expressed trkA (62.8 +/- 1.4%), neurofilament protein 68-kDa (64.8 +/- 1.5%) or glutamate alone (19.5 +/- 1.9%). SP was always expressed in trkA-positive neurons. Based on the extent of co-localization of SP with the receptors TRPV1 and trkA in DRG airway neurons, the present study indicates that the DRG pathway may have effects on the magnitude of neurogenic inflammation in airway diseases such as asthma.
Dinh
Q Thai
QT
Department of Medicine, Charité, School of Medicine, Humboldt University, Ostring 3, R. 3.0066, Augustenburger Platz 1, Berlin D-13353, Germany. q-thai.dinh@charite.de
Groneberg
David A
DA
Peiser
Christian
C
Mingomataj
Ervin
E
Joachim
Ricarda A
RA
Witt
Christian
C
Arck
Petra C
PC
Klapp
Burghard F
BF
Fischer
Axel
A
D000818:Animals; D001692:Biological Transport; D004396:Coloring Agents; D005260:Female; D005727:Ganglia, Spinal / Q000166:cytology / Q000378:metabolism*; D007473:Ion Channels / Q000378:metabolism*; D008168:Lung / Q000294:innervation; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009474:Neurons / Q000378:metabolism*; D020917:Receptor, trkA / Q000378:metabolism*; D011984:Sensory Receptor Cells / Q000166:cytology / Q000378:metabolism; D013373:Substance P / Q000378:metabolism*; D050916:TRPV Cation Channels; D014018:Tissue Distribution
D004396:Coloring Agents; D007473:Ion Channels; D050916:TRPV Cation Channels; C493921:TRPV1 protein, mouse; D013373:Substance P; D020917:Receptor, trkA