title: Interaction of endokinin A/B and (Mpa(6))-γ2-MSH-6-12 in pain regulation in mice.
abstract: The present study focused on the interactive effects of (Mpa(6))-γ2-MSH-6-12 (Mpa, spinal level) and endokinin A/B (EKA/B, supraspinal level) on pain regulation in mice. EKA/B (30 pmol) only weakened 100 pmol Mpa-induced hyperalgesia at 5 min, but could enhance it during 20-30 min. However, EKA/B (100 pmol) antagonized all dose levels of Mpa significantly at 5 min and blocked them completely at 10 min. EKA/B (3 nmol) co-injected with Mpa presented marked analgesia at 5 min and enduring hyperalgesia within 20-60 min. To investigate the underlying mechanisms between Mpa and EKA/B, SR140333B and SR142801 (NK1 and NK3 receptor antagonists, respectively) were utilized. SR140333B had no influence on Mpa, while SR142801 potentiated it during 20-30 min. Whereas, SR140333B and SR142801 could block the co-administration of Mpa and EKA/B (30 pmol) separately at 5 min and 30 min. These phenomena might attribute to that these two antagonists promoted the antagonism of EKA/B (30 pmol) at the early stage, while antagonized EKA/B preferentially in the latter period. SR140333B weakened the analgesia of EKA/B (3 nmol), but produced no effect on Mpa. However, SR140333B failed to affect the co-injection of Mpa and EKA/B, which implied that EKA/B cooperated with Mpa prior to SR140333B. These results could potentially help to better understand the interaction of NK and MrgC receptors in pain regulation in mice.
authors.affiliation: The Core Laboratory of the First Affiliated Hospital, Lanzhou University, 1 Donggang West Road, Lanzhou 730000, China; Key Laboratory for Gastrointestinal Diseases of Gansu Province, Lanzhou 730000, China. Electronic address: zhoulx@lzu.edu.cn.
authors.forename: Lanxia
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Institute of Biochemistry and Molecular Biology, School of Life Sciences, 222 Tianshui South Road, Lanzhou 730000, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Institute of Biochemistry and Molecular Biology, School of Life Sciences, 222 Tianshui South Road, Lanzhou 730000, China.
authors.forename: Chunbo
authors.initials: C
authors.lastname: He
authors.affiliation: Institute of Biochemistry and Molecular Biology, School of Life Sciences, 222 Tianshui South Road, Lanzhou 730000, China.
authors.forename: Chunnan
authors.initials: C
authors.lastname: Wei
authors.affiliation: Institute of Biochemistry and Molecular Biology, School of Life Sciences, 222 Tianshui South Road, Lanzhou 730000, China.
authors.forename: Yinliang
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Institute of Biochemistry and Molecular Biology, School of Life Sciences, 222 Tianshui South Road, Lanzhou 730000, China; Key Laboratory of Preclinical Study for New Drugs of Gansu Province, 222 Tianshui South Road, Lanzhou 730000, China. Electronic address: dongsl@lzu.edu.cn.
authors.forename: Shouliang
authors.initials: S
authors.lastname: Dong
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D006930:Hyperalgesia / Q000139:chemically induced / Q000188:drug therapy*; D007276:Injections, Intraventricular; D007278:Injections, Spinal; D008297:Male; D051379:Mice; D015288:Neurokinin A / Q000494:pharmacology*; D015287:Neurokinin B / Q000494:pharmacology*; D064729:Neurokinin-1 Receptor Antagonists / Q000494:pharmacology; D010146:Pain / Q000503:physiopathology*; D010147:Pain Measurement / Q000187:drug effects; D010880:Piperidines / Q000494:pharmacology; D018042:Receptors, Neurokinin-3 / Q000037:antagonists & inhibitors; D014326:Tropanes / Q000494:pharmacology; D019825:gamma-MSH / Q000037:antagonists & inhibitors* / Q000494:pharmacology*
chemical_list: D064729:Neurokinin-1 Receptor Antagonists; D010880:Piperidines; D018042:Receptors, Neurokinin-3; C526005:SR140333B; D014326:Tropanes; D019825:gamma-MSH; D015288:Neurokinin A; D015287:Neurokinin B; C091554:SR 142801
keywords: Co-injection; Endokinin A/B; Pain regulation; γ2-MSH-6–12