ZMIANY ZAWARTOŚCI GLIKOGENU W MÓZGU W DOŚWIADCZALNEJ ISCHEMII

Glycogen was quantitatively determined in brains of 10-week-old Wistar ratswith bilaterally ligated common carotid arteries, at 6, 12, 24, 48, 72, and 120 hafter artery ligation.The biochemical investigations were supplemented by histological and ultrastructuralstudies as well as by histochemical glycogen, determination. On the basisof the studies performed the following conclusions are drown:1. Bilateral common carotid artery ligation leads to a considerable rise of thebrain glycogen level without any signs of brain structural lesion. This increase isstatistically significant as compared with the control group after 12 h, and reachesits peak 48 h after artery ligation. For 5 days after the operation no return ofthe glycogen level to the initial value was observed.2. Histochemically noticeable unnormal glycogen deposits in the nerve tissueare found in the grey formations of the brain, and in 'the first place in the cortex,they are less frequent and appear only in earlier periods in the basal nuclei. Depositsin the white matter are extremely rare. Electron microscopic inspectionshows that polysaccharide deposits accumulate exclusively in the cytoplasm ofastrocytes and in their processes.3. Ether general anaesthaesia leads to a slight, but statistically significant riseof the brain glycogen level exclusively at 12 h after application of the anaesthetic.At a later time this influence is no more noticeable.The authors suggest that glycogen accumulation under conditions of moderatebrain ischemia is connected with defective glucose utilisation by the nervetissue.