A pharmacological model of cerebral ischemia. The effects of indomethacin on cerebral blood flow velocity, quantitative EEG and cognitive functions.

Indomethacin decreases cerebral blood flow. Such an effect in humans might offer the possibility to establish a human model of cerebral ischemia. In the present study the effects of a single oral dose of 100 mg indomethacin were studied in male subjects with quantitative electroencephalography, cerebral blood flow velocity and the memory comparison task as parameters. Twelve healthy male students (age 23.2 +/- 2.6 years) were studied. Before the test day the memory comparison task was performed twice (parallel versions). On the test day baseline recordings of quantitative electroencephalography were obtained, together with measurement of blood flow velocity. Ninety minutes after indomethacin ingestion recordings of quantitative electroencephalography and blood flow velocity were repeated and a parallel version of the memory comparison task was performed. The blood flow velocity decreased to 60% of the initial value; quantitative electroencephalography showed a -0.3 Hz slowing of the alpha peak frequency (p less than 0.01) and a decrease in the relative power of the alpha band (p less than 0.10) without any change in the delta or theta band. The memory comparison task showed an increase of the slope index (p less than 0.05), indicating a deterioration of cognitive functioning.