Kf. Sjolund et al., INTRATHECAL AND SYSTEMIC R-PHENYLISOPROPYLADENOSINE REDUCES SCRATCHING BEHAVIOR IN A RAT MONONEUROPATHY MODEL, NeuroReport, 7(11), 1996, pp. 1856-1860
THE aim of the present study was to investigate the effect of intraven
ous or intrathecal (i.t.) administration of R-phenylisopropyladenosine
(R-PIA), a selective A, adenosine receptor agonist, on spontaneous sc
ratching behaviour, a phenomenon presumably related to pain in a monon
europathy model (sciatic nerve ligation) in rats. The acute effect of
daily i.t. R-PIA injections was studied up to 21 days following nerve
ligation. The results demonstrate that both i.v. (30 nmol) and i.t. (3
nmol) R-PIA, in doses not producing any motor impairment, significant
ly reduces scratching behaviour in this animal model. The mechanism of
action for this presumed antinociceptive effect is suggested to occur
at the spinal cord level.