H. Homayoun et al., Effects of adenosine receptor agonists and antagonists on pentylenetetrazole-induced amnesia, EUR J PHARM, 430(2-3), 2001, pp. 289-294
The effect of adenosine agents on amnesia induced by pentylenetetrazole was
examined in mice. Post-training administration of pentylenetetrazole (50 a
nd 60 mg/kg) disrupted 24-h retention of a single-trial passive avoidance t
ask. The adenosine receptor antagonists, theophylline (2.5-25 mg/kg) and 8-
phenyltheophylline (0.5-2 mg/kg), administered 30 min before and just after
training at doses which did not affect retention, reduced the amnestic eff
ect of pentylenetetrazole in a dose-dependent manner. Post-training adminis
tration of the adenosine A(1) receptor agonists, N-6-cyclohexyladenosine (C
HA, 0.1 and 0.5 mg/kg) and N-6-phenylisopropyladenosine (R-PIA, 0.03 and 0.
1 mg/kg), but not the adenosine A, receptor agonist, 5'-N-ethylcarboxamidoa
denosine (NECA, 0.01 and 0.001 mg/kg), impaired retention. Nonamnestic dose
s of CHA and R-PIA potentiated the disruption induced by a lower dose of pe
ntylenetetrazole (40 mg/kg). NECA did not induce any response in this respe
ct. It is suggested that an adenosine A(1) receptor mechanism is involved i
n amnesia induced by pentylenetetrazole. (C) 2001 Published by Elsevier Sci
ence B.V.