Nitric oxide donor increases cerebral blood flow and oxygenation during kainic acid-induced seizures in newborn rabbits.

BACKGROUND: We investigated the hypothesis that sodium nitroprusside (SNP), a nitric oxide (NO) donor, increased the cerebral blood flow and oxygenation during kainic acid (KA)-induced seizures in newborn rabbits. METHODS: After KA administration (i.v. 12 mg/kg)to induce seizures, either 1.2 mg/kg SNP (SNP group, i.v., n = 6) or 1 mL normal saline (vehicle group, i.v., n = 6)was given. Regional cerebral blood flow (rCBF), cerebral oxyhemoglobin(oxy-Hb), deoxyhemoglobin (deoxy-Hb), total hemoglobin (t-Hb), mean arterial blood pressure (MABP), heart rate (HR) and electroencephalography(EEG) were continuously monitored throughout the experiment, lasting at least 60 min after the KA administration. RESULTS: The value for rCBF was greatly increased during seizures in the SNP group than in the vehicle group. The values for oxy-Hb and t-Hb were significantly increased, and deoxy-Hb was significantly decreased. There were ameliorations of cerebral oxygenation in the SNP group during the acute phase of seizures in the neonatal animals, compared with the vehicle group. There were no significant differences in the MABP, HR, arterial blood gases, rectal and brain temperatures, blood hemoglobin concentrations,blood glucose levels, the latencies to first abnormal discharges in EEG, the total sum of the duration of abnormal discharges in EEG and the incidences of subclinical electric status epileptics between the two groups. CONCLUSIONS: These results suggest that the treatment with SNP contributed to the increases in cerebral blood flow and oxygenation, and that EEG abnormalities were unchanged by the treatment with SNP during neonatal seizures.