Seizures were induced in 7-day-old rats by intraperitoneal injection of DL-homocysteine thiolactone. Phosphocreatine (PCr), ATP, glucose, glycogen and lactate were determined in the cerebral cortex during various intervals after injection, corresponding to the early, as well as long periods of seizure activity. The unchanged levels of ATP, a very mild PCr decline and a pronounced accumulation of lactate (in the face of modest changes in brain glucose and glycogen) were observed. These results suggest that the immature rat brain is able to compensate energy expenditure associated with seizure activity by increased energy production, mainly due to increased anaerobic glycolysis. It remains to be determined whether a similar conclusion is also valid for other brain regions, e.g. subcortical structures.
As a consequence of enhanced production of oxygen free radicals, lipid peroxidation leads to the degradation of membrane lipids and disturbances of membrane permeability. Lipid peroxidation increases under stress conditions such as hypoxia, ischemia or acidosis as well as in metabolic diseases, e.g. diabetes mellitus. We have shown that subcomatous doses of insulin (6.0 IU/kg) significantly increase thiobarbituric acid reactive substances (TBARs), especially malondialdehyde (MDA) - the endproduct of lipid peroxidation, in the brain and heart of mice. In our model of insulin-induced hypoglycemia, mice were treated with the neuroprotective, peptide-containing drug Cerebrolysin (100 mg/kg b.w.). Animals were sacrificed by decapitation two or three hours after the injection of tested substance and samples were taken to determine several serum parameters (glucose, total protein, triglycerides and lactic acid) and TBARs in the brain and heart. Although Cerebrolysin was not able to affect serum parameters after subcomatous insulin injection, the drug significantly influenced lipid peroxidation. A single injection of Cerebrolysin already decreased TBARs levels in the brain and heart tissue. Presuming that an increase of TBARs reflects disturbances of the cell membrane, we have documented a promising effect of Cerebrolysin on cell integrity., J. Patočková, M. Kršiak, P. Marhol, E. Tůmová., and Obsahuje bibliografii
napsal Bohuslav Horák., KČSN, Na obálce uvedeno: Geografický seminář c. k. České university, Obsahuje bibliografické odkazy, and Separát z: Sborníku České společnosti zeměvědné, roč. 6. a 7.