Proconvulsant effect of papaverine on theophylline-induced seizures in rats.

1. The effects of papaverine, an adenosine uptake inhibitor, were tested against theophylline-induced seizures. 2. Rats were infused with a constant intravenous infusion of theophylline at 10.3 mg/min immediately following intraperitoneal pretreatment with either papaverine 35 mg/kg or saline vehicle. 3. Papaverine produced a potent proconvulsant effect towards theophylline seizures, reducing the onset time and cumulative dose to seizure and theophylline concentrations in arterial serum, cerebrospinal fluid and brain, respectively, at onset of maximal seizures.