Effects of spinally and supraspinally injected 3-isobutyl-1-methylxanthine, cholera toxin, and pertussis toxin on cold water swimming stress-induced antinociception in the mouse.
1. The cold (4 degrees C) water swimming stress (CWSS) for 3 min significantly increased the inhibition of the tail-flick response in ICR mice. 2. Pertussis toxin (PTX, 0.05-0.5 microgram) in mice pretreated intrathecally (IT) for 6 days attenuated the inhibition of the tail-flick response induced by CWSS. However, intracerebroventricular (ICV) pretreatment with PTX at the same doses did not affect CWSS-induced inhibition of the tail-flick inhibition. 3. 3-Isobutyl-1-methylxanthine (IBMX, 0.01-1 ng) in mice pretreated IT for 10 min dose-dependently attenuated the inhibition of the tail-flick response induced by CWSS. However, IBMX in mice ICV pretreated ICV at the same doses was not effective in attenuating the CWSS-induced inhibition of the tail-flick response. 4. Neither IT nor ICV pretreatment with cholera toxin (CTX, 0.05-0.5 microgram) for 24 hr affected the inhibition of the tail-flick response induced by CWSS. 5. The ICV or IT injection of PTX, CTX, or IBMX did not affect the basal tail-flick response latency. 6. It is concluded that spinal, but not supraspinal, PTX-sensitive G-proteins and cAMP phosphodiesterase may be involved in the antinociception produced by CWSS. However, neither spinal nor supraspinal CTX-sensitive G-proteins appear to be involved in mediating the antinociception induced by CWSS.
Suh
H W
HW
Department of Pharmacology, College of Medicine, Hallym University, Kangwon-Do, Korea.
Song
D K
DK
Kwon
S H
SH
Kim
K W
KW
Min
B H
BH
Kim
Y H
YH
D015056:1-Methyl-3-isobutylxanthine / Q000008:administration & dosage*; D000818:Animals; D002772:Cholera Toxin / Q000008:administration & dosage*; D019204:GTP-Binding Proteins / Q000187:drug effects / Q000502:physiology*; D007276:Injections, Intraventricular; D007278:Injections, Spinal; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D017288:Pain Threshold / Q000187:drug effects / Q000502:physiology*; D037342:Pertussis Toxin; D010726:Phosphodiesterase Inhibitors / Q000008:administration & dosage*; D013312:Stress, Physiological / Q000188:drug therapy / Q000503:physiopathology*; D010566:Virulence Factors, Bordetella / Q000008:administration & dosage*
D010726:Phosphodiesterase Inhibitors; D010566:Virulence Factors, Bordetella; D002772:Cholera Toxin; D037342:Pertussis Toxin; D019204:GTP-Binding Proteins; D015056:1-Methyl-3-isobutylxanthine