Relation between the Severity of the Sensorimotor Cortical Edema with Cell Swelling and the Duration of Common Carotid Artery Occlusion in Rats (Morphometric Study)

The aim of the study. To examine the changes in structure and morphometry in sensorimotor cortical edema with cell swelling in mature white rats after common carotid artery occlusion of various durations.Material and methods. Acute ischemia was modeled on white adult Wistar rats by 20-, 30- and 40-min occlusion of the common carotid arteries (CCA). Histological (hematoxylin-eosin and Nissl staining), immunohistochemical (NSE, MAP-2, GFAP) and morphometric methods were used. Morphometry was assessed on hematoxylin and eosin-stained specimens using ImageJ 1.53 plug-ins (Find Maxima, Find Foci). Statistical hypothesis testing (nonparametric criteria) was performed using Statistica 8.0 software.Results. In the sensorimotor cortex (SMC) of white rats after 20, 30 and 40 minutes of CCA occlusion the signs of cytotoxic brain edema appeared, focal destructive and adaptive changes of neurons and astroglia evolved. The edema persisted throughout the observation period (7 days). The increase in the relative area, the number of cell swelling zones and their hydration (pixel brightness) was significant. On days 1 and 3 after CCA occlusion, some of the SMC astrocyte processes underwent destruction. Subpial and perivascular zones suffered to a greater extent. Mild and moderate (after unilateral 30-min CCA occlusion) to moderate and severe (after bilateral 40-min CCA occlusion) scattered structural and functional changes of the SMC with large areas of clearing in the «porous» neuropil, severe perivascular and perineuronal edema of the astrocyte processes developed. The latter was associated with a moderate reduction of the total neuronal density.Conclusion. After occlusion of CCA, signs of edema with cellular swelling appeared in the SMC amid dystrophic and necrotic pyramidal neurons and activated neuroglial cells. To a greater extent, the signs of brain swelling were evident three days after bilateral 40-min occlusion of CCA

Common Carotid Artery Occlusion and Double-Nucleated Cellular Structures In The Rat Sensorimotor Cerebral Cortex

The aim of the study. To study the double-nucleated cellular structures of the brain sensorimotor cortex (SMC) of sexually mature white rats after a 40-minute occlusion of the common carotid arteries.Methods. Acute ischemia was simulated in white Wistar rats by 40-minute occlusion of the common carotid arteries (OCCA). We performed comparative morphometric evaluation of cyto-, dendro-, synapto-, and glioar-chitectonics of the neocortex in intact animals (n=5), and 1 (n=5), 3 (n=5), and 7 days (n=5) after OCCA. We used Nissl, hematoxylin and eosin staining, and immunohistochemical reactions for NSE, MAP-2, HSP-70, p38, caspase-3, GFAP, AIF1, and Ki-67. Numerical density of pyramidal neurons, oligodendrocytes (ODCs), mi-croglyocytes (MGCs), presence of dystrophic and necrobiotic neurons with one or more nucleoli, hetero- and dikaryons were assessed. Statistical hypotheses were tested using Statistica 8.0 software.Results. The percentage of dystrophic and necrobiotic neurons, nerve cells with two nuclei or two or more nucleoli, the total number (proliferation) and percentage of hypertrophic astrocytes, ODCs and MGCs increased significantly after OCCA. The total numerical density of SMC neurons decreased by 26.4% (P=0.001) in layer III and by 18.5% in layer V (Mann-Whitney U Test; P=0.01) after OCCA throughout the observation period. Pathological and compensatory changes were diffusely focal and more pronounced in layer III of the neocortex. The density of bi-nucleated heterokaryons and dikaryons remained unchanged on days 1 and 3 after OCCA vs control and was 3.5 (1.5-4.0)/mm2, and increased to 6.5 (5.0-8.5)/mm2 on day 7 (Mann-Whitney U Test; P=0.002). This increase occurred along with a higher density of ODCs and MGCs than in the control. The maximum number of neurons with two or more nucleoli was also noted in layer III and V during this period.Conclusion. After 40-minute OCCA in SMC, parallel to the dystrophic and necrobiotic changes of pyramidal neurons and activation of neuroglial cells, there was an increase in the formation of heterokaryons and neurons with amplified nucleolus. These changes were considered as a variant of neuronal response to ischemic damage

Морфофункциональная характеристика гиппокампа белых крыс в остром периоде после тяжелой черепно-мозговой травмы на фоне применения L-лизина эсцината

Aim of study. The study is devoted to the effect of L-lysine aescinat on the nervous tissue of the CA1 and CA3 fields of the hippocampus of the brain of white rats in the acute period after severe traumatic brain injury (TBI).Material and methods. TBI was simulated by applying a blow to the parieto-occipital region with a freely falling weight weighing 200-250 grams from a height of 50 cm using a special rail rack. The objectives of the study were: 1) comparative morphometric assessment of the degree of hydration, cyto- and glioarchitectonics of different layers of CA1 and CA3 fields after ischemia without treatment; 2) the effect of L-lysine aescinat on these indicators. We used histological (staining of sections with hematoxylin-eosin and Nissl), immunohistochemical (for NSE, MAP-2 and GFAP) and morphometric methods. On thin (4 μm) serial frontal sections of the hippocampus, neurons, astrocytes, microvessels and neuropiles were studied in control (intact animals, n=5) and 1 and 3 days after injury without treatment (n=10, comparison group) and with treatment ( n = 10, main group). The number density of neurons was determined using the Nissl staining of cells and by the reaction to NSE. The cytoskeleton of neurons was studied by detecting MAP-2, and astroglia by GFAP. On color raster images (staining with hematoxylin and eosin, x100) using the Find Maxima plug-in filter, the zones of maximum brightness were determined, which were then analyzed using Analyze Particles from the ImageJ 1.52s program. Zones of maximum brightness corresponded to areas of the hippocampus with a high degree of hydration of the nervous tissue - edema-swelling. The nature of the distribution, statistical hypotheses, and plotting were checked using Statistica 8.0 software and R environment.Results. In control animals, normochromic neurons without signs of changes in the cytoskeleton prevailed in all layers of fields CA1 and CA3, and a low degree of hydration of the nervous tissue was noted (the relative proportion of zones of maximum brightness was 5–8%). One and 3 days after TBI, there was a statistically significant increase in the focal content of dystrophic and necrobiotically altered neurons (95% confidence interval: 52–78%), manifestations of reactive gliosis were noted, and the proportion of zones of maximum brightness increased to 16%. Statistically significant layer-by-layer differences were revealed between the CA1 and CA3 fields of the hippocampus. The use of L-lysine aescinat had a statistically significant effect on the morphometric parameters of the nervous tissue of the hippocampus.Conclusion. In the early post-traumatic period after TBI, the degree of hydration of the nervous tissue of the hippocampus increased. Heteromorphicity of dystrophic and necrobiotic changes in different layers of CA1 and CA3 fields was noted. L-lysine aescinate had a statistically significant positive effect on these changes. To a greater extent, this is typical for the CA3 field. The revealed changes are considered not only as patho-, but also as sanogenetic structural mechanisms of protection and reorganization of the hippocampus in the acute post-traumatic period.1. In the acute period (1−3 days) after severe traumatic brain injury, the degree of hydration of all components of the hippocampal nervous tissue increased. In the group without treatment, 3 days after injury, the relative volume of edema-swelling zones varied from 10 to 13% in CA1 (control 3-7%) and from 8 to 16% in CA3 (control 5–10%).2. The heteromorphism of hydropic changes in the molecular layer, the layer of pyramidal neurons and the polymorphic layer was established. The maximum increase in the volume of free water (more than twofold) was characteristic of the molecular and polymorphic layer CA1, as well as the polymorphic layer CA3.3. The use of L-lysine aescinat in the acute period significantly changed the manifestations of hydropic dystrophy. One day after injury, the volume of free water increased in comparison with animals without treatment, and then, after 3 days, decreased, but remained higher than in the comparison group. The maximum effect of the drug was noted in field CA3.Цель исследования. Исследование посвящено изучению влияния L-лизина эсцината на нервную ткань полей СА1 и СА3 гиппокампа головного мозга белых крыс (Wistar) в остром периоде после тяжелой черепно- мозговой травмы (ТЧМТ).Материал и методы. ТЧМТ моделировали нанесением на теменно-затылочную область удара свободно падающим грузом массой 200−250 г с высоты 50 см с помощью специальной рельсовой стойки. Задачами исследования были: 1) сравнительная морфометрическая оценка степени гидратации, цито- и глиоархитектоники различных слоев полей СА1 и СА3 после ТЧМТ без лечения; 2) влияние на эти показатели L-лизина эсцината. Использованы гистологические (окраска срезов гематоксилином- эозином и по Нисслю), иммуногистохимические (на NSE, MAP-2 и GFAP) и морфометрические методы. На тонких (4 мкм) серийных фронтальных срезах гиппокампа изучены нейроны, астроциты, микрососуды и нейропиль в контроле (интактные животные, n=5) и через 1 и 3 суток после травмы без лечения (n=10, группа сравнения) и с лечением (n=10, основная группа). Численную плотность нейронов определяли с помощью окраски клеток по Нисслю и реакции на NSE. Цитоскелет нейронов изучали с помощью реакции на МАР-2, а астроглии — GFAP. На цветных растровых изображениях (окраска гематоксилином и эозином, объектив х100) с помощью плагин-фильтра “Find Maxima” определяли зоны максимальной яркости (ЗМЯ), которые затем анализировали с помощью “Analyze Particles” из программы ImageJ 1.52s. ЗМЯ соответствовали участкам гиппокампа с высокой степенью гидратации нервной ткани — отек-набухание. Характер распределения, статистические гипотезы, построение графиков проверяли с помощью программ Statistica 8.0 и среды R.Результаты. У контрольных животных во всех слоях полей СА1 и СА3 превалировали нормохромные нейроны без признаков изменения цитоскелета, отмечена низкая степень гидратации нервной ткани (относительная доля ЗМЯ 5−8%). Через 1 и 3 суток после ТЧМТ статистически значимо увеличивалось очаговое содержание дистрофически и некробиотически измененных нейронов (95% доверительный интервал: 52−78%), отмечались проявления реактивного глиоза, а доля ЗМЯ увеличивалась до 16%. Выявлены статистически значимые послойные различия между полями СА1 и СА3 гиппокампа. Применение L-лизина эсцината оказывало статистически значимое влияние на морфометрические показатели нервной ткани гиппокампа.Заключение. В раннем периоде после ТЧМТ увеличивалась степень гидратации нервной ткани гиппокампа. Отмечена гетероморфность дистрофических и некробиотических изменений в разных слоях полей СА1 и СА3. L-лизин эсцинат статистически значимо влиял на эти изменения. В большей степени это характерно для поля СА3. Выявленные изменения рассматриваются не только как пато-, но и как саногенетические структурные механизмы защиты и реорганизации гиппокампа в посттравматическом периоде.Выводы.1. В остром периоде (1−3 суток) после тяжелой черепно-мозговой травмы увеличивалась степень гидратации всех компонентов нервной ткани гиппокампа. В группе без лечения через 3 суток после травмы относительный объем зон отека-набухания варьировался от 10 до 13% в СА1 (контроль 3−7%) и от 8 до 16% — в СА3 (контроль 5−10%).2. Установлена гетероморфность гидропических изменений в молекулярном слое, слое пирамидных нейронов и полиморфном слое. Максимальное увеличение объема свободной воды (более чем в 2 раза) было характерно для молекулярного и полиморфного слоя СА1, а также полиморфного слоя СА3.3. Применение в остром периоде L-лизина эсцината способствовало статистически значимому изменению проявлений гидропической дистрофии. Через 1 сутки после травмы объем свободной воды увеличивался в сравнении с животными без лечения, а затем, спустя 3 суток, уменьшался, но оставался выше, чем в группе сравнения. Максимальное влияние препарата отмечено в поле СА3

Glial Cell Architecture Dynamics in Dentate Gyrus and CA4 Area of Wistar Rat Hippocampus Following 20-minute Occlusion of Common Carotid Arteries

Aim. To study the distribution and spatial organization of dentate gyrus (DG) astrocytes and CA4 area of hippocampus of Wistar rats following 20-minute occlusion of common carotid arteries (OCCA) compared to sham-operated control animals.Material and methods. Histological (Nissl staining with hematoxylin and eosin), immunohistochemical (GFAP, MAP-2) and morphometric methods were used. Astrocytes and neurons in control (sham-operated animals, n = 5) group, after 6 hours (n=5), 1 days (n=5), 3 days (n=5), 7 days (n=5), 14 days (n=5) and 30 days (n=5) after 20-minute OCCA were studied on thin (4 µm) serial frontal sections of the hippocampus. Fractal analysis (ImageJ 1.52; fraclac 2.5 plugin) was used to obtain additional quantitative information on the spatial organization of astrocyte networks. Statistical hypotheses were tested using nonparametric criteria.Results. 30 days after the 20-minute OCCA, only 5.3% of CA4 neurons were irreversibly destroyed and the total numerical density of DG granular cells remained at the control level. Hypertrophy and increased complexity of the spatial organization of astrocyte processes were observed 6 hours and 1 day after OCCA and persisted for 30 days. Astrogliosis was accompanied by an increased relative area of GFAP-positive material and fractal dimension and reduced lacunarity of the astrocyte network. The latter was especially evident in 1, 14 and 30 days after the OCCA.Conclusion. After the 20-minute OCCA, the density of GFAP-positive material increased, the fibroarchitecture reorganized and gained more complexity due to the branching of astrocyte processes. At the same time, the total numerical density of neurons changed only slightly. All this indicated the probable role of astrocytes in post-ischemic activation of natural neuroprotection mechanisms

Проявление отека-набухания сенсомоторной коры большого мозга крыс в зависимости от длительности окклюзии общих сонных артерий (морфометрическое исследование)

The aim of the study. To examine the changes in structure and morphometry in sensorimotor cortical edema with cell swelling in mature white rats after common carotid artery occlusion of various durations.Material and methods. Acute ischemia was modeled on white adult Wistar rats by 20-, 30- and 40-min occlusion of the common carotid arteries (CCA). Histological (hematoxylin-eosin and Nissl staining), immunohistochemical (NSE, MAP-2, GFAP) and morphometric methods were used. Morphometry was assessed on hematoxylin and eosin-stained specimens using ImageJ 1.53 plug-ins (Find Maxima, Find Foci). Statistical hypothesis testing (nonparametric criteria) was performed using Statistica 8.0 software.Results. In the sensorimotor cortex (SMC) of white rats after 20, 30 and 40 minutes of CCA occlusion the signs of cytotoxic brain edema appeared, focal destructive and adaptive changes of neurons and astroglia evolved. The edema persisted throughout the observation period (7 days). The increase in the relative area, the number of cell swelling zones and their hydration (pixel brightness) was significant. On days 1 and 3 after CCA occlusion, some of the SMC astrocyte processes underwent destruction. Subpial and perivascular zones suffered to a greater extent. Mild and moderate (after unilateral 30-min CCA occlusion) to moderate and severe (after bilateral 40-min CCA occlusion) scattered structural and functional changes of the SMC with large areas of clearing in the «porous» neuropil, severe perivascular and perineuronal edema of the astrocyte processes developed. The latter was associated with a moderate reduction of the total neuronal density.Conclusion. After occlusion of CCA, signs of edema with cellular swelling appeared in the SMC amid dystrophic and necrotic pyramidal neurons and activated neuroglial cells. To a greater extent, the signs of brain swelling were evident three days after bilateral 40-min occlusion of CCA.Цель исследования. Изучить структурные изменения и дать морфометрическую характеристику проявлениям отека-набухания сенсомоторной коры (СМК) большого мозга половозрелых белых крыс после окклюзии общих сонных артерий различной продолжительности.Методы исследования. Острую ишемию моделировали на белых взрослых крысах Wistar путем 20, 30 и 40-мин окклюзии общих сонных артерий (ООСА). Использовали гистологические (окраска гематоксилин-эозином и по Нисслю), иммуногистохимические (NSE, MAP-2, GFAP) и морфометрические методы исследования. Морфометрический анализ осуществляли на препаратах, окрашенных гематоксилин-эозином, с помощью плагинов программы ImageJ 1.53 (Find Maxima, Find Foci). Проверку статистических гипотез (непараметрические критерии) проводили в программе Statistica 8.0.Результаты. В СМК головного мозга белых крыс после 20, 30 и 40-мин ООСА появлялись признаки цитотоксического отека-набухания, развивались очаговые деструктивные и адаптивные изменения нейронов и астроглии. Проявления отека-набухания сохранялись на протяжении всего периода наблюдения (7 сут). Статистически значимо увеличивалась относительная площадь, количество зон отека-набухания и степень их гидратации (яркость пикселей). Через 1 и 3 сут после ООСА часть отростков астроцитов СМК разрушалась. В большей степени страдали субпиальная и периваскулярные зоны. После односторонней 30 мин ООСА развивались слабые и умеренные, а после двусторонней 40 мин ООСА — умеренные и выраженные мелкоочаговые структурно-функциональные изменения СМК с появлением больших зон просветления «пористого» нейропиля, выраженного периваскулярного и перинейронального отека отростков астроцитов. Последнее сочеталось с умеренной редукцией общей численной плотности нейронов.Заключение. После ООСА в СМК на фоне дистрофических и некробиотических изменений пирамидных нейронов и активации нейроглиальных клеток появлялись признаки отека-набухания. В большей степени это проявлялось через 3 сут после двусторонней 40 мин окклюзии