title: Effect of saikosaponin A on maintenance of intravenous morphine self-administration.
abstract: In this study, we investigated the effects of saikosaponin A (SSA), a major compound of Bupleurum falcatum L., on morphine self-administration behavior. Male Sprague-Dawley rats were trained to self-administer intravenous morphine (0.1mg/kg per injection over 5s) during daily 1-h sessions under a fixed-ratio 1 schedule. Rats were pretreated with SSA (0.25, 0.5, 1.0mg/kg) by intraperitoneal injection 30 min prior to the start of the test session. Results demonstrated that pretreatment with SSA reduced morphine-maintained responding dose-dependently. Additionally, SSA inhibition of morphine-reinforced behavior was blocked by the selective GABA(B) receptor antagonist (2S)(+)-5,5-dimethyl-2-morpholineacetic acid (SCH 50911), but not the selective GABA(A) receptor antagonist bicuculline. Together, these results suggest that SSA may effectively suppress morphine-reinforced behavior by activating GABA(B) receptors.
authors.affiliation: Department of Physiology, College of Oriental Medicine, Daegu Haany University, Daegu 706-828, Republic of Korea.
authors.forename: Seong Shoon
authors.initials: SS
authors.lastname: Yoon
authors.forename: Hey Soo
authors.initials: HS
authors.lastname: Kim
authors.forename: Hea-Young
authors.initials: HY
authors.lastname: Cho
authors.forename: Jaesuk
authors.initials: J
authors.lastname: Yun
authors.forename: Eun Yong
authors.initials: EY
authors.lastname: Chung
authors.forename: Choon-Gon
authors.initials: CG
authors.lastname: Jang
authors.forename: Kwang Joong
authors.initials: KJ
authors.lastname: Kim
authors.forename: Chae Ha
authors.initials: CH
authors.lastname: Yang
mesh_terms: D000818:Animals; D003213:Conditioning, Psychological / Q000187:drug effects* / Q000502:physiology*; D004347:Drug Interactions; D007262:Infusions, Intravenous; D008297:Male; D009020:Morphine / Q000008:administration & dosage*; D009828:Oleanolic Acid / Q000008:administration & dosage / Q000031:analogs & derivatives*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012054:Reinforcement, Psychology; D012503:Saponins / Q000008:administration & dosage*; D012646:Self Administration
chemical_list: D012503:Saponins; D009828:Oleanolic Acid; D009020:Morphine; C025759:saikosaponin D