Pathological Study on Amyloidosis : Localized Deposition of Amylid; Dystrophic or Age-dependent Amyloid

The effects of sciatic nerve stimulation on the electroencephalogram (EEG), cerebral metabolic rate for oxygen (CMRo_2) and cerebral blood flow (CBF) were investigated at five different levels of thiopental anesthesia. Thiopental was infused intravenously at the constant rate of 23 mg/kg/hour for 2 hours, and anethetic levels at 10 (plasma concentration of thipental 15±2 μg/mg), 30(27±3), 60(37±6), 90(42±6) and 120 minutes (49±6) after the start of infusion were designated levels I, II, III, IV and V, respectively. With increasing dose of thiopental, the EEG changed from fast wave activeity to irregular slow wave acticity and then burst suppression. These EEG changes were accompanied by the progressive reduction of CMRo_2 and CBF, decreasing to 58 and 59 per cent of the value before thiopental at level V, respectively. The effects of stimulation for 5 minutes were tested at each level. At level I the mean CMRo_2 and CBF increased to 110 and 107 per cent of control, respectively, accompanied by EEG activation. At level II the CMRo_2 and CBF increased at 1 minute to 106 and 107 per cent of control, respectively, accompanied unchanged. These results suggest that tight coupling between the EEG, CMRo_2 and CBF exists during thiopental anesthesia.

amyloidosis

dystrophic amyloid

aging

β-fibrilloses