[Effect of S-adenosyl-L-methionine sulfate tosylate (FO-1561) on functional recovery after transient cerebral ischemia in rats].
The present investigation was undertaken to examine the recovery of functions, spontaneous EEG activity and cerebral ATP content during blood recirculation following cerebral ischemia in rats. The ischemia was induced by bilateral carotid artery 30 min-occlusion 24 hr after the permanent electrocauterization of bilateral vertebral arteries. EEG spectral analysis was performed by the Berg transform. The recovery of EEG activity was assessed by the time elapsing from the onset of blood recirculation until the delta (0.5-4 Hz), theta (4-8 Hz), alpha (8-13 Hz) or beta (13-32 32 Hz) band reappeared and the relative proportion of the four bands at 45 and 60 min after recirculation. Following the 20 min recirculation, the brains were frozen in situ with liquid nitrogen and then stored at -80 degrees C for later extraction for analysis. Concentrations of ATP in the cerebral cortex were determined with enzymatic methods. In animals administered FO-1561 (10 approximately 100 mg/kg, i.v.) simultaneously with blood recirculation, the reduction of time elapsing until reappearance of the theta, alpha and beta bands, the decrease in proportion of the delta band and the increase in that of the theta, alpha and beta bands which indicated the facilitation of transition to the normal state were observed. In animals administered FO-1561 (100 mg/kg), the improvement of ATP content was detected. These results demonstrate that FO-1561 may have a beneficial effect on the recovery from dysfunctions due to cerebrovascular disorder.