title: Peptide 19-containing neurons in the medullary dorsal horn, subnuclei interpolaris and oralis, and nucleus principalis of the rat.
abstract: Peptide 19 (PEP 19) is a 7.6 kDa polypeptide which can bind to calmodulin and inhibit calcium-calmodulin signaling. In this study, PEP 19-immunoreactivity (ir) was examined in the rat trigeminal sensory nuclei. Numerous PEP 19-immunoreactive (ir) neurons were detected in the medullary dorsal horn (MDH) and rostral parts of the trigeminal sensory nuclei (subnuclei interpolaris and oralis, and nucleus principalis). The mean numbers ± S.D. per section of PEP 19-ir neurons were 104.2 ± 30.4 in the MDH, 137.8 ± 39.5 in the subnucleus interpolaris, 129.2 ± 46.9 in the subnucleus oralis and 157.2 ± 34.1 in the nucleus principalis. In the MDH, small to medium-sized PEP 19-ir neurons were abundant within superficial laminae. PEP 19-ir neurons with various cell body sizes were also distributed in the rostral parts of the trigeminal sensory nuclei. A double immunofluorescence analysis also demonstrated that many PEP 19-ir neurons co-expressed parvalbumin (PV)-ir in the MDH (9.0%), subnucleus oralis (7.7%) and nucleus principalis (19.7%). In the subnucleus interpolaris, such neurons were relatively rare (1.7%). PEP 19-ir neurons were mostly devoid of calbindin D-28k. In addition, a retrograde tracing method revealed that a substantial number of PEP 19-ir neurons projected to the thalamus. PV-ir was common in thalamus-projecting PEP 19-ir neurons. These findings suggest that PEP 19-ir neurons in the MDH may have a function in modulation of nociceptive and thermo-receptive signaling. It is also likely that PEP 19-ir neurons in rostral parts of the trigeminal sensory nuclei are related to transduction of mechano-receptive information from facial regions to the thalamus.
authors.affiliation: Division of Oral and Craniofacial Anatomy, Graduate School of Dentistry, Tohoku University, Sendai, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Suzuki
authors.forename: Tadasu
authors.initials: T
authors.lastname: Sato
authors.forename: Rika
authors.initials: R
authors.lastname: Sasaki
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ichikawa
mesh_terms: D000818:Animals; D008297:Male; D010455:Peptides / Q000378:metabolism*; D020671:Posterior Horn Cells / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014018:Tissue Distribution; D014278:Trigeminal Nuclei / Q000378:metabolism*; D002148:Calmodulin-Binding Proteins; D009419:Nerve Tissue Proteins
chemical_list: D010455:Peptides; C119195:Edf1 protein, rat; D002148:Calmodulin-Binding Proteins; D009419:Nerve Tissue Proteins