Effects of spinally and supraspinally injected 3-isobutyl-1-methylxanthine, cholera toxin, and pertussis toxin on immobilization stress-induced antinociception in the mouse.
The effects of intracerebroventricular (i.c.v.) and intrathecal (i.t.) 3-isobutyl-1-methylxanthine (IBMX), cholera toxin (CTX) and pertussis toxin (PTX) administration on immobilization-induced antinociception were studied in ICR mice. Antinociception was assessed by the tail-flick assay. Immobilization of the mouse increased inhibition of the tail-flick response for at least 1 h. The pretreatment with i.t. IBMX (0.01-1 ng), but not i.c.v. IBMX, significantly attenuated immobilization-induced inhibition of the tail-flick response. The pretreatments with i.c.v. PTX (0.05-0.5 microg) as well as i.t. CTX, but neither i.c.v. CTX (0.05-0.5 microg) nor i.t. PTX, potentiated the inhibition of the tail-flick response induced by immobilization stress. Our results suggest that spinally located phosphodiesterase appears to be involved in the production of immobilization stress-induced antinociception. In addition, inactivation of supraspinally located PTX-sensitive G-proteins and spinally located CTX-sensitive G-proteins may modulate immobilization stress-induced antinociception.
Chung
Ki M
KM
Department of Pharmacology, Institute of Natural Medicine, College of Medicine, Hallym University, 1 Okchun-dong, Chunchon, Kangwon Do, 200-702, South Korea.
Choi
Seong S
SS
Choi
Mi R
MR
Suh
Hong W
HW
D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology*; D000704:Analysis of Variance; D000818:Animals; D002772:Cholera Toxin / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D007103:Immobilization; D007276:Injections, Intraventricular / Q000379:methods; D007278:Injections, Spinal / Q000379:methods; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009043:Motor Activity; D010147:Pain Measurement / Q000187:drug effects; D017288:Pain Threshold / Q000187:drug effects* / Q000502:physiology; D037342:Pertussis Toxin / Q000494:pharmacology*; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology*; D011930:Reaction Time; D013312:Stress, Physiological / Q000503:physiopathology*; D013997:Time Factors
D010726:Phosphodiesterase Inhibitors; D002772:Cholera Toxin; D037342:Pertussis Toxin; D015056:1-Methyl-3-isobutylxanthine