PMID- 91402
OWN - NLM
STAT- MEDLINE
DCOM- 19800119
LR  - 20181113
IS  - 0007-1188 (Print)
IS  - 0007-1188 (Linking)
VI  - 67
IP  - 1
DP  - 1979 Sep
TI  - Methyl xanthines, adenosine 3',5'-cyclic monophosphate and the spinal 
      transmission of nociceptive information.
PG  - 51-7
AB  - 1 In spinal cats anaesthetized with either alpha-chloralose or sodium 
      pentobarbitone, a study was made of the effects of adenosine 3',5'-cyclic 
      monophosphate (cyclic AMP), mono- and di-butyryl cyclic AMP and the methyl 
      xanthines, theophylline and isobutyl methyl xanthine (IBMX), on the responses of 
      neurones of laminae I, IV and V to noxious and innocuous skin stimuli. The 
      compounds were administered from micropipettes positioned in the substantia 
      gelatinosa. IBMX was also given intravenously.2 When administered in the 
      substantia gelatinosa, neither cyclic AMP, its butyryl derivatives, nor the 
      methyl xanthines had any effect on the excitation of neurones of spinal laminae 
      IV and V by noxious heating of the skin or deflection of hairs. When the 
      nociceptive responses of cells had been reduced by electrophoretic morphine, 
      methyl xanthines and cyclic AMP failed to modify the effects of morphine on these 
      deeper neurones. Electrophoretically administered naloxone reversed the effect of 
      morphine.3 Intravenously administered IBMX (1 to 2 mg/kg) produced large 
      transient increases in the firing rate of both C fibres and the excitation of 
      dorsal horn neurones by noxious heating of the skin. These increases coincided 
      with decreases in the mean systemic blood pressure, and probably resulted from 
      increased temperatures being attained in the dermis by each noxious stimulus. 
      When dorsal horn neurones were activated by electrical stimulation of the tibial 
      nerve by a stimulus adequate to excite C fibres, intravenous IBMX produced a 
      small or no increase in the number of spikes per stimulus.4 These results in the 
      spinal cord do not support the hypothesis that the inhibition of synthesis of 
      cyclic AMP is relevant to the analgesic action of morphine in mammals.
FAU - Duggan, A W
AU  - Duggan AW
FAU - Griersmith, B T
AU  - Griersmith BT
LA  - eng
PT  - Journal Article
PL  - England
TA  - Br J Pharmacol
JT  - British journal of pharmacology
JID - 7502536
RN  - 0 (Xanthines)
RN  - C137DTR5RG (Theophylline)
RN  - E0399OZS9N (Cyclic AMP)
RN  - TBT296U68M (1-Methyl-3-isobutylxanthine)
SB  - IM
MH  - 1-Methyl-3-isobutylxanthine/pharmacology
MH  - Animals
MH  - Cats
MH  - Cyclic AMP/*pharmacology
MH  - Injections, Intravenous
MH  - Pain/*physiopathology
MH  - Spinal Cord/*physiology
MH  - Substantia Gelatinosa/physiology
MH  - Synaptic Transmission/*drug effects
MH  - Theophylline/pharmacology
MH  - Time Factors
MH  - Xanthines/*pharmacology
PMC - PMC2043597
EDAT- 1979/09/01 00:00
MHDA- 1979/09/01 00:01
PMCR- 1980/09/01
CRDT- 1979/09/01 00:00
PHST- 1979/09/01 00:00 [pubmed]
PHST- 1979/09/01 00:01 [medline]
PHST- 1979/09/01 00:00 [entrez]
PHST- 1980/09/01 00:00 [pmc-release]
PST - ppublish
SO  - Br J Pharmacol. 1979 Sep;67(1):51-7.