Spinally-mediated antinociception is induced in mice by an adenosine kinase-, but not by an adenosine deaminase-, inhibitor.
Relative involvement of adenosine deaminase and adenosine kinase in antinociception induced by endogenous adenosine was investigated. Antinociception induced by 5'-amino 5'-deoxyadenosine (5'-ADAdo; an adenosine kinase inhibitor) and deoxycoformycin (dCF; an adenosine deaminase inhibitor) administered i.t. was determined using the mouse tail-flick assay. Dose- and time-dependent antinociception was observed following i.t. administration of 5'-ADAdo, but not dCF. Antinociception induced by 5'-ADAdo was reversed by coadministration i.t. of theophylline, an adenosine receptor antagonist, in a dose-dependent manner. These data provide preliminary evidence that adenosine kinase plays a more significant physiological role than adenosine deaminase in the regulation of adenosine involved in spinally-mediated antinociception.
Keil
G J
GJ
College of Pharmacy, Oregon State University, Corvallis 97331.
DeLander
G E
GE
D000241:Adenosine / Q000502:physiology; D000243:Adenosine Deaminase / Q000502:physiology; D058892:Adenosine Deaminase Inhibitors; D000248:Adenosine Kinase / Q000037:antagonists & inhibitors* / Q000502:physiology; D000818:Animals; D003839:Deoxyadenosines / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D008297:Male; D051379:Mice; D009619:Nociceptors / Q000187:drug effects*; D010147:Pain Measurement; D015649:Pentostatin / Q000494:pharmacology*; D013116:Spinal Cord / Q000187:drug effects* / Q000502:physiology; D013997:Time Factors
D058892:Adenosine Deaminase Inhibitors; D003839:Deoxyadenosines; C057928:5'-amino-5'-deoxyadenosine; D015649:Pentostatin; D000248:Adenosine Kinase; D000243:Adenosine Deaminase; D000241:Adenosine