title: Distribution of hemokinin-1 in the rat trigeminal ganglion and trigeminal sensory nuclear complex.
abstract: OBJECTIVE
  A new mammalian tachykinin peptide encoded in a TAC4 gene was identified and designated as hemokinin-1 (HK-1). A representative of the tachykinin peptide family is substance P (SP), and the function of SP has been well characterized as a pain transmitter or modulator, while it is possible that HK-1 is involved in pruriceptive processing, but, as yet, the distribution of HK-1 peptide in the trigeminal sensory system is still unknown. Thus, the aim of the present study was to elucidate the distribution of HK-1, while comparing the expression of SP, in the trigeminal ganglion and trigeminal sensory nuclear complex.
  
  
  METHODS
  The trigeminal ganglion and the brain stem of male SD rats were used in the immunohistochemical study. Since the amino acid sequence in the carboxyl-terminal regions of HK-1 and SP is common, polyclonal antibodies of HK-1 and SP derived from 6 amino acids consisting of amino-terminal regions of these peptides were produced in guinea pig and rabbit, respectively. The immunohistochemical staining of HK-1 and SP was conducted using frozen sections of the trigeminal ganglion and brain stem in rats.
  
  
  RESULTS
  Immunohistochemical studies revealed the expression of HK-1 in small- and medium-sized trigeminal ganglion neurons, in the paratrigeminal nucleus, and in lamina I of the trigeminal nucleus caudalis, while there was no immunoreactivity of HK-1 in the trigeminal nucleus principalis, trigeminal nucleus oralis, and trigeminal nucleus interpolaris.
  
  
  CONCLUSIONS
  These findings indicate that HK-1 is a target molecule for treatment of itch in the orofaicial regions.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan.
authors.forename: Kaori
authors.initials: K
authors.lastname: Igawa
authors.affiliation: Department of Psychiatry, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Funahashi
authors.affiliation: Department of Psychiatry, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Miyahara
authors.affiliation: Department of Neuroscience, Section of Integrative Physiology, Faculty of Medicine, University of Miyazaki, Kihara 5200, Kiyotake, Miyazaki 889-1692, Japan.
authors.forename: Rumi
authors.initials: R
authors.lastname: Naono-Nakayama
authors.affiliation: Department of Psychiatry, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan.
authors.forename: Hisae
authors.initials: H
authors.lastname: Matsuo
authors.affiliation: Department of Oral and Maxillofacial Surgery, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Yamashita
authors.affiliation: Department of Oral and Maxillofacial Surgery, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan.
authors.forename: Sumio
authors.initials: S
authors.lastname: Sakoda
authors.affiliation: Department of Psychiatry, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan.
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Nishimori
authors.affiliation: Department of Psychiatry, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan. Electronic address: ishiday@med.miyazaki-u.ac.jp.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Ishida
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D034961:Antigens, Nuclear / Q000378:metabolism; D001933:Brain Stem / Q000166:cytology / Q000378:metabolism; D006168:Guinea Pigs; D007150:Immunohistochemistry; D008297:Male; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009474:Neurons / Q000378:metabolism*; D010146:Pain / Q000378:metabolism; D011537:Pruritus / Q000378:metabolism; D011817:Rabbits; D051381:Rats; D017207:Rats, Sprague-Dawley; D066148:Spinal Cord Dorsal Horn / Q000166:cytology / Q000378:metabolism; D013373:Substance P / Q000378:metabolism; D015320:Tachykinins / Q000378:metabolism*; D014275:Trigeminal Caudal Nucleus / Q000378:metabolism; D012668:Trigeminal Ganglion / Q000166:cytology* / Q000378:metabolism*
chemical_list: D034961:Antigens, Nuclear; D009419:Nerve Tissue Proteins; C546339:Rbfox3 protein, rat; D015320:Tachykinins; C507968:hemokinin-1; D013373:Substance P
keywords: Hemokinin-1; Immunohistochemistry; Pruritus; Substance P; Trigeminal ganglion; Trigeminal sensory nuclear complex