title: KiSS-1 expression and metastin-like immunoreactivity in the rat brain.
abstract: Metastin, the gene product of metastasis suppressor gene KiSS-1, is the endogenous ligand for the G-protein-coupled receptor GPR54 (or AXOR12, or OT7T175). The expression of KiSS-1 gene and peptide and the distribution of metastin were studied in the rat central nervous system by reverse transcriptase-polymerase chain reaction, Western blotting, and immunohistochemical methods. KiSS-1 gene and peptide expression was higher in the hypothalamus than in the brainstem and spinal cord. In the brain, metastin-like immunoreactivity (irMT) was found mainly in three groups of cells: dorsomedial hypothalamic nucleus, nucleus of the solitary tract, and caudal ventrolateral medulla. Immunoreactive fibers of varying density were noted in bed nucleus of stria terminalis, septal nuclei, nucleus accumbens, caudate putamen, diagonal band, amygdala, hypothalamus, zona incerta, thalamus, periaqueductal gray, raphe nuclei, lateral parabrachial nucleus, locus coeruleus, spinal trigeminal tract, rostral ventrolateral medulla, and medullary reticular nucleus. Preabsorption of the antiserum with metastin peptide fragment (45-54)-NH2 (1 microg/ml) resulted in no staining in any of the sections. The biological activity of metastin was assessed by monitoring intracellular calcium [Ca2+]i in cultured hippocampal neurons, which are known to express GPR54. Metastin increased [Ca2+]i in a population of cultured hippocampal neurons. The results show that metastin is biologically active in rat central neurons, and its anatomical distribution suggests a possible role in nociception and autonomic and neuroendocrine functions.
authors.affiliation: Department of Pharmacology, East Tennessee State University, Johnson City, Tennessee 37614, USA. gbrailou@temple.edu
authors.forename: G Cristina
authors.initials: GC
authors.lastname: Brailoiu
authors.forename: Siok L
authors.initials: SL
authors.lastname: Dun
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ohsawa
authors.forename: Deling
authors.initials: D
authors.lastname: Yin
authors.forename: Jun
authors.initials: J
authors.lastname: Yang
authors.forename: Jaw Kang
authors.initials: JK
authors.lastname: Chang
authors.forename: Eugen
authors.initials: E
authors.lastname: Brailoiu
authors.forename: Nae J
authors.initials: NJ
authors.lastname: Dun
mesh_terms: D000818:Animals; D001369:Axons / Q000378:metabolism / Q000648:ultrastructure; D001921:Brain / Q000033:anatomy & histology / Q000378:metabolism*; D001931:Brain Mapping; D002118:Calcium / Q000378:metabolism; D020013:Calcium Signaling / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D004302:Dorsomedial Hypothalamic Nucleus / Q000166:cytology / Q000378:metabolism; D005260:Female; D015870:Gene Expression / Q000187:drug effects / Q000502:physiology; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism; D007150:Immunohistochemistry; D059648:Kisspeptins; D008297:Male; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D011506:Proteins / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D043562:Receptors, G-Protein-Coupled; D000074502:Receptors, Kisspeptin-1; D018013:Receptors, Neuropeptide / Q000378:metabolism; D012154:Reticular Formation / Q000166:cytology / Q000378:metabolism; D017552:Solitary Nucleus / Q000166:cytology / Q000378:metabolism
chemical_list: C491406:Kiss1 protein, rat; C492247:Kiss1r protein, rat; D059648:Kisspeptins; D011506:Proteins; D012333:RNA, Messenger; D043562:Receptors, G-Protein-Coupled; D000074502:Receptors, Kisspeptin-1; D018013:Receptors, Neuropeptide; D002118:Calcium