Effect of pentylenetetrazol treatment on cholecystokinin mRNA and peptide levels in rat hippocampus and cortex

After treatment with pentylenetetrazol (PTZ), cholecystokinin (CCK) mRNA and CCK-like immunoreactivity (CCK-LI) levels were determined in rat hippocampus and cortex at different time points. In the temporal cortex treatment with 60 mg/kg PTZ, i.p., induced increases of CCK mRNA and CCK-LI levels at 2 days after the injection. In the hippocampus, a similar increase of CCK mRNA level was observed on the second day. By contrast, in the frontal cortex, CCK-LI level was increased at 10 days after the treatment with PTZ. These data show that PTZ increases both CCK mRNA and CCK-LI levels in these rat brain regions at different time.