title: Evaluation of interaction between intrathecal adenosine and MK801 or NBQX in a rat formalin pain model.
abstract: Adenosine and excitatory amino acids have been known to be involved in modulating nociceptive transmission at the spinal level. The authors assessed the characteristics of the interaction of the adenosine-excitatory amino acid antagonist combinations in the spinal cord of rats on the formalin-induced nociception. Intrathecal NMDA antagonist ((5R, 10S)-(+)-5-methyl-10,11-dihydro-(5)H-dibenzo[a[,]d]cyclohepten-5,10-imine hydrogen maleate, MK801, 30 microg) and AMPA antagonist (2,3-dioxo-6-nitro-1,2,3,4-tetrahydrobenzo[F]quinoxaline-7-sulfonamide, NBQX, 3 microg) decreased the total number of flinches during both phases in the formalin test. Intrathecal adenosine (300 microg) had little effect on the phase 1 flinching response, but decreased the phase 2 response. The fixed dose analysis and the isobolographic analysis revealed that adenosine interacts additively with MK801 and NBQX in the spinal cord.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Chonnam National University, Medical School, Gwangju, Korea. mhyoon@chonnam.ac.kr
authors.forename: Myung Ha
authors.initials: MH
authors.lastname: Yoon
authors.forename: Hong Beom
authors.initials: HB
authors.lastname: Bae
authors.forename: Jeong Il
authors.initials: JI
authors.lastname: Choi
authors.forename: Seong Wook
authors.initials: SW
authors.lastname: Jeong
authors.forename: Sung Su
authors.initials: SS
authors.lastname: Chung
authors.forename: Kyung Yeon
authors.initials: KY
authors.lastname: Yoo
authors.forename: Chang Young
authors.initials: CY
authors.lastname: Jeong
authors.forename: Seok Jae
authors.initials: SJ
authors.lastname: Kim
authors.forename: Sung Tae
authors.initials: ST
authors.lastname: Chung
authors.forename: Chang Mo
authors.initials: CM
authors.lastname: Kim
authors.forename: Tae Hun
authors.initials: TH
authors.lastname: An
mesh_terms: D000241:Adenosine / Q000008:administration & dosage / Q000494:pharmacology* / Q000502:physiology; D000818:Animals; D004195:Disease Models, Animal; D016291:Dizocilpine Maleate / Q000494:pharmacology*; D004357:Drug Synergism; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology*; D005557:Formaldehyde; D007278:Injections, Spinal; D008297:Male; D016202:N-Methylaspartate / Q000037:antagonists & inhibitors; D010146:Pain / Q000139:chemically induced / Q000503:physiopathology*; D011810:Quinoxalines / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000037:antagonists & inhibitors
chemical_list: D018691:Excitatory Amino Acid Antagonists; D011810:Quinoxalines; C062865:2,3-dioxo-6-nitro-7-sulfamoylbenzo(f)quinoxaline; D005557:Formaldehyde; D016202:N-Methylaspartate; D016291:Dizocilpine Maleate; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; D000241:Adenosine