title: Functional roles of endogenous D-serine in pain-induced ultrasonic vocalization.
abstract: The N-methyl-D-aspartate receptor (NMDAR) is crucial for pain-related behaviors. D-Serine is synthesized from L-serine by serine racemase (SR) and modulates NMDAR functions by acting as an agonist at the glycine-binding site. We analyzed noxious stimulus-induced ultrasonic vocalization and locomotor activity in the open-field test using SR knockout (SR-KO) mice to examine the role of endogenous D-serine in mammalian behaviors. SR-KO mice emitted less ultrasonic vocalization after noxious stimulation (VAS) than wild-type (WT) mice. The locomotor activity of WT mice decreased with repeated daily exposures to the open field, whereas that of SR-KO mice remained unchanged. VAS was significantly enhanced during arthritis in WT mice, whereas it was not enhanced during arthritis in SR-KO mice. These results indicate that mice lacking the ability to produce D-serine endogenously in the brain differ from normal mice with respect to the chronic pain-induced behavioral changes.
authors.affiliation: Department of Physiology and Biological Information, Dokkyo Medical University School of Medicine, Mibu, Japan.
authors.forename: Hitomi
authors.initials: H
authors.lastname: Tsuzuki
authors.forename: Masao
authors.initials: M
authors.lastname: Maekawa
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Konno
authors.forename: Yuuichi
authors.initials: Y
authors.lastname: Hori
mesh_terms: D000818:Animals; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009043:Motor Activity / Q000502:physiology; D010146:Pain / Q000378:metabolism* / Q000473:pathology; D012694:Serine / Q000502:physiology*; D014465:Ultrasonics / Q000379:methods; D014828:Vocalization, Animal / Q000502:physiology*
chemical_list: D012694:Serine