Дослідження активності ферментів антиоксидантної системи у корі великих півкуль головного мозку за моделювання геморагічного інсульту

Abstract

У статті наведено результати експериментального дослідження по оцінці метаболічних змін у корі мозку при інсульті. Щурам моделювали локальний геморагічний інсульт та вводили лікарські засоби (пірацетам, ліпін з кверцетином та їх комбінація). Біохімічними методами оцінювали активність супероксиддисмутази, каталази, глутатіонпероксидази і глутатіонредуктази. Результати досліджень показали збільшення активності каталази і зменшення активності глутатіонпероксидази і глутатіонредуктази на тлі інсульту. Введення ліпіну з кверцетином позначилося вираженим збільшенням активності глутатіонпероксидази і глутатіонредуктази; В статье приведены результаты экспериментального исследования по оценке метаболических изменений в коре головного мозга при инсульте. Крысам моделировали локальный геморрагический инсульт и вводили лекарственные средства (пирацетам, липин с кверцетином и их комбинация). Биохимическими методами оценивали активность супероксиддисмутазы, каталазы, глутатионпероксидазы и глутатионредуктазы. Результаты исследований показали увеличение активности каталазы и уменьшение активности глутатионпероксидазы и глутатионредуктазы на фоне инсульта. Введение липина с кверцетином сказало существенную активацию глутатионпероксидазы и глутатионредуктазы; In the experimental study we have used 45 male rats WKY line (average weight 220-250 g). Animals were divided into 5 groups: group 1 - intact rats (n=7); group 2 - rats with hemorrhagic stroke (n=12); group 3 - rats with hemorrhagic stroke which were injected with piracetam (n=8); group 4 - rats with hemorrhagic stroke which were injected with lecithin (Lipin) and quercetin (n=10); group 4 - rats with hemorrhagic stroke which were injected with combination of drugs (n=8). Hemorrhagic stroke was simulated in the right hemisphere of rat’s brain by injection of autoblood in the internal capsule. The drugs were injected intraperitoneally 2 hours later after making stroke at the following schemes and doses: piracetam (100 mg/kg, during 10 days), quercetin (7,2 mg/kg, during 5 days), lecithin (Lipin) (10 mg/kg, during 5 days), saline (0,02 ml/day, during 10 days). The activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR) in the cerebral cortex were studied. Localization of intracerebral hematoma was examined by histological method. According to the results of histological study the hematomas in the right internal capsule of the brain were found in 100% of operated rats. The hematoma’s size on the front slices was 6,1±0,4 mm2. The biochemical study results in the group of animals with stroke (group 2) identified the enzymes of antioxidant system activity changes. The CAT activity increased comparing with the control (group 1) average by 13,5% (p<0,05), while GPx and GR values were less than 32,2% (p=0,05) and 40,3% (p<0,05). After the SOD activity analysis the statistically significant difference with the control group was not found. In this way we could speak about compensatory activation of free radicals (reactive oxygen species) enzymatic utilization and the violation of glutathione metabolism at the same time, whereas the glutathione is main acceptor of low-cytotoxic molecules. In the group 3 we marked the normalization of CAT and GR activity. The values of SOD and GPx approached the control (p=0,05). The increased level of GR activity comparing with the group 2 was detected (average 60,7%, p<0,01). In the group 4 the level of SOD decreased by 14,9% (p<0,05) while the CAT level did not differ from the control. At the same time we found a strong activation of GPx in 3,2 times and GR in 3,1 times (p<0,01). In the group 5 the tendency to reduction of GPx activity was marked (p=0,05). The activity of other enzymes did not differ from the control group. Thus, the results of biochemical studies indicate the activity of antioxidant enzymes changes in the brain after stroke. The increased levels of CAT and decreased levels of GR are manifestations of cytoprotective mechanisms imbalance because both of these enzymes are taken part at neutralizing of free radicals through the hydrogen peroxide utilization and restoring the glutathione pool. At the same time using drugs supports the partial recovery while lecithin (Lipin) and quercetin even increase the activity of antioxidant enzymes.