Noradrenaline modulates the spontaneous firing activities of Purkinje cells via α2-adrenergic receptor in mouse cerebellar cortex / 生理学报

Cerebellar Purkinje cells (PCs) exhibit two types of discharge activities: simple spike (SS) and complex spike (CS). Previous studies found that noradrenaline (NA) can inhibit CS and bidirectionally regulate SS, but the enhancement of NA on SS is overwhelmed by the strong inhibition of excitatory molecular layer interneurons. However, the mechanism underlying the effect of NA on SS discharge frequency is not clear. Therefore, in the present study, we examined the mechanism underlying the increasing effect of NA on SS firing of PC in mouse cerebellar cortex in vivo and in cerebellar slice by cell-attached and whole-cell recording technique and pharmacological methods. GABAA receptor was blocked by 100 µmol/L picrotoxin in the whole process. In vivo results showed that NA significantly reduced the number of spikelets of spontaneous CS and enhanced the discharge frequency of SS, but did not affect the discharge frequency of CS. In vitro experiments showed that NA reduced the number of CS spikelets and after hyperpolarization potential (AHP) induced by electrical stimulation, and increased the discharge frequency of SS. NA also reduced the amplitude of excitatory postsynaptic current (EPSC) of parallel fiber (PF)-PC and significantly increased the paired-pulse ratio (PPR). Application of yohimbine, an antagonist of α2-adrenergic receptor (AR), completely eliminated the enhancing effect of NA on SS. The α2-AR agonist, UK14304, also increased the frequency of SS. The β-AR blocker, propranolol, did not affect the effects of NA on PC. These results suggest that in the absence of GABAA receptors, NA could attenuate the synaptic transmission of climbing fiber (CF)-PC via activating α2-AR, inhibit CS activity and reduce AHP, thus enhancing the SS discharge frequency of PC. This result suggests that NA neurons of locus coeruleus can finely regulate PC signal output by regulating CF-PC synaptic transmission.

Cortical Brain Functions ­ The Brodmann Legacy in the 21st Century

In 1909, Korbinian Brodmann described 52 functional brain areas, 43 of them found in the human brain. More than a century later, his devoted functional map was incremented by Glasser et al in 2016, using functional nuclear magnetic resonance imaging techniques to propose the existence of 180 functional areas in each hemisphere, based on their cortical thickness, degree of myelination (cortical myelin content), neuronal interconnection, topographic organization, multitask answers, and assessment in their resting state. This opens a huge possibility, through functional neuroanatomy, to understand a little more about normal brain function and its functional impairment in the presence of a disease.

Cerebral Amyloid Quantification in Cognitively Normal Korean Adults Using F-18 Florbetaben PET / 대한핵의학회잡지

PURPOSE: To investigate regional cerebral amyloid beta retention in cognitively normal Korean adults using F-18 florbetaben (FBB).METHODS: We prospectively analyzed F-18 FBB positron emission tomography (PET)/CT scans of 30 cognitively healthy adults (age range, 50??0 years) using automated quantification. The standardized uptake value ratios (SUVRs) of F-18 FBB were calculated for predefined regions by normalizing the regional count with cerebellar cortex.RESULTS: The distribution of amyloid beta for each brain region revealed no age-related trends (p > 0.05). From all subjects, mean SUVR of amyloid deposit was 1.30 ± 0.18. The right parietal lobe showed the highest SUVR value (1.46 ± 0.23), whereas the right frontal lobe and left precuneus showed the lowest SUVR (1.23 ± 0.25).CONCLUSIONS: We provide reference values of normative data obtained from healthy elderly Koreans and suggest its use for accurate diagnosis of patients with Alzheimer's disease.

Immunoreactivity of PCNA in the Cerebellum of Developing Guinea Pig

The investigation of the embryonic development of the cerebellum has a long history. The postnatal normal development of the cerebellum in rodents and other animals became a popular topic for morphological investigations nearly a century ago. However, surprisingly, only a few studies are available regarding the prenatal normal development of the rodent cerebellum, especially in guinea pigs. Cell proliferation is essential for the development of the nervous system. The assessment of cell proliferation can be achieved by using various methods. In this study, we investigated the cell proliferation of the cerebellar cortex in guinea pigs at different stages of pregnancy and in postnatal life. Fetuses were obtained by cesarean section at 50 or 60 days of gestation (dg). Immunohistochemistry was performed with proliferating cell nuclear antigen (PCNA) antibody in the cerebellum. Strong PCNA immunoreactivity was observed in the external granular layer (EGL), which is a neurogenic zone in the cerebellum. The proportion of PCNA-IR cells was greater at 1 week than at 60 dg in lobule I, but not lobule VIII. After 50 dg, the width of the EGL continued to decline until 1 week, due to the maturation of the EGL cells. These results demonstrate the pattern of PCNA immunoreactivity in the developing cerebellum of guinea pigs. This serves as a guideline to study abnormal cerebellum development.

Intravenous Anesthetic, Propofol Affects Synaptic Responses in Cerebellar Purkinje Cells

OBJECTIVE: Propofol is an intravenously administered anesthetic that enhances γ-aminobutyric acid-mediated inhibition in the central nerve system. Other mechanisms may also be involved in general anesthesia. Propofol has been implicated in movement disorders. The cerebellum is important for motor coordination and motor learning. The aim of the present study was to investigate the propofol effect on excitatory synaptic transmissions in cerebellar cortex. METHODS: Excitatory postsynaptic currents by parallel fiber stimulation and complex spikes by climbing fiber stimulation were monitored in Purkinje cells of Wister rat cerebellar slice using whole-cell patch-clamp techniques. RESULTS: Decay time, rise time and amplitude of excitatory postsynaptic currents at parallel fiber Purkinje cell synapses and area of complex spikes at climbing fiber Purkinje cell synapses were significantly increased by propofol administration. CONCLUSION: The detected changes of glutamatergic synaptic transmission in cerebellar Purkinje cell, which determine cerebellar motor output, could explain cerebellar mechanism of motor deficits induced by propofol.

The Emerging Concept of Intrinsic Plasticity: Activity-dependent Modulation of Intrinsic Excitability in Cerebellar Purkinje Cells and Motor Learning

What is memory? How does the brain process the sensory information and modify an organism's behavior? Many neuroscientists have focused on the activity- and experience-dependent modifications of synaptic functions in order to solve these fundamental questions in neuroscience. Recently, the plasticity of intrinsic excitability (called intrinsic plasticity) has emerged as an important element for information processing and storage in the brain. As the cerebellar Purkinje cells are the sole output neurons in the cerebellar cortex and the information is conveyed from a neuron to its relay neurons by forms of action potential firing, the modulation of the intrinsic firing activity may play a critical role in the cerebellar learning. Many voltage-gated and/or Ca²⁺-activated ion channels are involved in shaping the spiking output as well as integrating synaptic inputs to finely tune the cerebellar output. Recent studies suggested that the modulation of the intrinsic excitability and its plasticity in the cerebellar Purkinje cells might function as an integrator for information processing and memory formation. Moreover, the intrinsic plasticity might also determine the strength of connectivity to the sub-cortical areas such as deep cerebellar nuclei and vestibular nuclei to trigger the consolidation of the cerebellar-dependent memory by transferring the information.

Estudio histomorfométrico de la corteza cerebelosa con microscopia holográfica digital / Histomorphometric study of the cerebellar cortex with digital holographic microscopy

Se realizó un estudio descriptivo y transversal de la corteza cerebelosa humana, desde el punto de vista histomorfométrico, desde enero hasta septiembre del 2015, con el empleo de la microscopia holográfica digital instalada en el Departamento de Holografía Digital de la Universidad de Oriente en Santiago de Cuba, con vistas efectuar mediciones que permitieran establecer comparaciones con otros estudios. Los cálculos mostraron el grosor de las capas molecular y granulosa, el área, el perímetro, los diámetros mayores y menores del cuerpo y el núcleo de las células de Purkinje. Asimismo, se tomaron imágenes holográficas en tres dimensiones, que posibilitaron concluir la existencia de parámetros determinados mediante este procedimiento, los que no habían sido notificados y que resultan de interés en el estudio histológico de la corteza cerebelosa

A descriptive and cross-sectional study of the human cerebellar cortex, from the histomorphometric point of view, was carried out from January to September, 2015, using the digital holographic microscopy installed in the Digital Holography Department of Oriente University in Santiago de Cuba, aimed at making measurings that allowed to establish comparisons with other studies. The calculations showed the thickness of the molecular and granular layers, the area, perimeter, greatest and smallest diameters of the body and Purkinje cells nucleus. Also, holographic images in three dimensions were taken, that facilitated to conclude the existence of certain parameters by means of this procedure, those that had not been notified and are of interest in the histological study of the cerebellar cortex

Quantitative study on human cerebellar cortex from anatomy cadaver preparations / Estudio cuantitativo de la corteza del cerebelo humano a partir de la anatomía de preparaciones cadavéricas

Human cerebellum is important for motor coordination; muscle tones and maintaing the equilibrium of the body. In our region, limited data is available on the normal morphology of human cerebellum, whilst fresh biopsy is quite difficult to obtain. Here adult male cerebellum from cadaver anatomy preparations embalmed with 37 % formalin fixative solution for over a year are studied (n=3). After removal, right cerebellum hemisphere was sliced into cubicle then temporary soaked into 50-60 % of alcohol before being paraffinated. Two parasagittal adjacent slices from each sample were deparaffinated (5 µm) and then stained with hematoxyllin-eosin (HE). Slides were observed under light microscope (Olympus, Japan). Pictures were analysed from 6 field numbers of each, with Optilab and Image Raster 3 software (Indonesia). The density of the Purkinje cells (Neuron purkinjense), the number and density of the Purkinje cells and the thickness of the molecular layer are measured. Data were analysed with the level of significance of p<0.05 (ANOVA, Microsoft Excel 2007). The distance between 2 Purkinje cells is ranged between 82.6-346.6 µm, although no significant differences found (p=0.1). There are no significant differences in the number and in the density of the Purkinje cells amongst samples (p=0.72 and 0.34, respectively); might be due to the similar age, sex and race of these cadavers. However, there is a significant difference in the thickness of the molecular layer (p=0.015). Variations amongst individual cerebelli are observed, with a significant different thickness in the molecular layer. The cellular composition of each cerebellum is unique, arguably correlated to the individual cerebellum activity when alive.

El cerebelo humano es importante en la coordinación motora, los tonos musculares y el mantenimiento del equilibrio del cuerpo. En nuestra región, son limitados los datos disponibles en relación a la morfología normal del cerebelo humano, por otra parte obtener una biopsia fresca es bastante difícil de obtener. Para este trabajo se utilizaron tres cerebelos adultos de sexo masculino, obtenidos a partir de cadáveres conservados con una solución de formalina al 37 % durante más de un año. Después de la separación, el hemisferio derecho del cerebelo fue seccionado en cubos que fueron posteriormente impregnados en una solución de 50-60 % de alcohol antes del proceso de parafinización. Se tomaron dos secciones parasagitales adyacentes (5 µm) de cada muestra desparafinada y luego éstas fueron teñidas con Hematoxilina-Eosina. Las muestras se observaron al microscopio óptico (Olympus, Japón). Se analizaron 6 campos por muestra con los softwares Optilab e Image Raster 3 (Indonesia). Se midieron la densidad de las neuronas purkinjenses (células de Purkinje), el número y densidad de ellas y el espesor de la capa molecular. Los datos fueron analizados con un nivel de significación de p<0,05 (ANOVA, Microsoft Excel 2007). La distancia entre dos células de Purkinje varió entre 82,6-346,6 µm, sin encontrarse diferencias significativas (p = 0,1). No hay diferencias significativas en el número (p = 0,72) y la densidad (p = 0,34) de células de Purkinje entre las muestras; podría deberse a la misma edad, el sexo y la raza de los cadáveres utilizados. Sin embargo, hay una diferencia significativa en el espesor de la capa molecular (p = 0,015). Se observaron variaciones individuales en el cerebelo, encontrándose diferencia significativa el espesor de la capa molecular. La composición celular del cerebelo es única, sin duda esta se correlaciona con la actividad del cerebelo en individuos vivos.

CD44 Expression in Microglia of the Retina and Cerebellum of Developing and Adult Chicken / 체질인류학회지

CD44 is a transmembrane protein that acts as a receptor for an adhesion molecule, hyaluronic acid. The type of cells expressing CD44 and roles of CD44 are still controversial and need to be elucidated. The aim of the present study was to examine the type of cells expressing CD44 and the changes in their distribution in the retina and the cerebellum of the developing and adult chicken. Embryonic day 14 (E14) and post-hatch day 90 (P90) chickens were used in this study. CD44-immunoreactive (ir) cells were observed both in the retina and the cerebellum of the two developmental stages examined. In the retina of E14, CD44-ir cells were mainly located in the nerve fiber layer. In adults, most of the CD44-ir cells were in the nerve fiber layer and some were dispersed in other layers of the retina. In the cerebellum of E14, CD44-ir cells were distributed throughout the cerebellar cortex, including the external and internal granular layers. CD44-ir cells were more frequently found in the cerebellum of P90 adult chickens than in that of E14 embryos. At higher magnification, CD44-ir cells showed ramified cytoplasmic processes irradiating from their cell bodies. In the retina and in the cerebellum of all ages examined, double staining showed that most of the CD44-ir cells also expressed RCA-1, a marker of microglia. In contrast to that, at the same locations, GFAP and CD44 were not co-expressed in cells. When the adult retina was stimulated by LPS, CD44 immunoreactivity increased, and CD44-ir cells were also RCA-1-positive. The present results indicated that CD44 was expressed in microglia of the retina and the cerebellum of the developing and adult chicken even in normal conditions, and microglial CD44 expression was increased upon LPS stimulation.

Evaluation of brachial plexus fascicles involvement on infraclavicular block: unfixed cadaver study / Avaliação do envolvimento dos fascículos do plexo braquial no bloqueio por via infraclavicular: estudo em cadáveres não fixados / Evaluación de la implicación de los fascículos del plexo braquial en el bloqueo por vía infraclavicular: estudio en cadáveres no fijos

BACKGROUND AND OBJECTIVES: This study shows how the diffusion of the anesthetic into the sheath occurs through the axillary infraclavicular space and hence proves the efficacy of the anesthetic block of the brachial plexus, and may thereby allow a consolidation of this pathway, with fewer complications, previously attached to the anesthesia. MATERIALS AND METHODS: 33 armpits of adult cadavers were analyzed and unfixed. We injected a solution of neoprene with latex dye in the infraclavicular space, based on the technique advocated by Gusmão et al., and put the corpses in refrigerators for three weeks. Subsequently, the specimens were thawed and dissected, exposing the axillary sheath along its entire length. RESULTS AND DISCUSSION: Was demonstrated involvement of all fasciculus of the plexus in 51.46%. In partial involvement was 30.30%, 18.24% of cases the acrylic was located outside the auxiliary sheath involving no issue. CONCLUSIONS: The results allow us to establish the infraclavicular as an effective and easy way to access plexus brachial, because the solution involved the fascicles in 81.76% partially or totally, when it was injected inside the axillary sheath. We believe that only the use of this pathway access in practice it may demonstrate the efficiency. .

JUSTIFICATIVA E OBJETIVOS: Procuramos demonstrar como ocorre a difusão do anestésico no interior da bainha axilar, quando se utiliza o bloqueio por via infraclavicular, através da fossa infraclavicular e, consequentemente, provar a eficácia dessa via, podendo, com isso, permitir uma consolidação da utilização desse acesso, com redução das complicações. MATERIAS E MÉTODO: Foram utilizadas 33 axilas de cadáveres adultos não fixados. Injetamos uma solução de neoprene látex com corante na fossa infraclavicular, baseando-se na técnica preconizada por Gusmão e col, e colocamos os cadáveres em geladeiras por três semanas. Posteriormente, as peças foram descongeladas e dissecadas, expondo a bainha axilar em toda sua extensão. RESULTADOS E DISCUSSÃO: Foi demonstrado envolvimento de todos os fascículos do plexo em 51,46%. Em 30,30% houve envolvimento parcial, e em 18,24% dos casos o acrílico foi localizado fora da bainha axilar, não envolvendo nenhum fascículo. CONCLUSÕES: Os dados obtidos permitem estabelecer a via infraclavicular como uma via eficaz e de fácil acesso ao plexo braquial, visto que a solução injetada envolveu os fascículos em 81,76% parcialmente ou totalmente, quando era injetada dentro da bainha axilar. Acreditamos que apenas a utilização desta via de acesso na prática poderá demonstrar a eficiência da mesma. .

JUSTIFICACIÓN Y OBJETIVOS: Este estudio intenta demostrar cómo ocurre la difusión del anestésico en el interior de la vaina axilar, cuando se utiliza el bloqueo por vía infraclavicular a través de la fosa infraclavicular, y al mismo tiempo, probar la eficacia de esa vía, pudiendo así permitir una consolidación de la utilización de ese acceso con reducción de las complicaciones. MATERIALES Y MÉTODO: Fueron utilizadas 33 axilas de cadáveres adultos no fijadas. Inyectamos una solución de neopreno látex con colorante en la fosa infraclavicular, con la técnica preconizada por Gusmão et al., y colocamos los cadáveres en frigoríficos durante 3 semanas. Posteriormente, las piezas fueron descongeladas y disecadas, exponiendo la vaina axilar en toda su extensión. RESULTADOS Y DISCUSIÓN: Quedó demostrada la implicación de todos los fascículos del plexo en un 51,46%. En un 30,30% hubo una participación parcial, y en un 18,24% de los casos el acrílico fue ubicado fuera de la vaina axilar sin la participación de ningún fascículo. CONCLUSIONES: Los datos obtenidos permiten establecer la vía infraclavicular como una vía eficaz y de fácil acceso al plexo braquial, visto que la solución inyectada tuvo la participación de los fascículos en un 81,76% parcial o totalmente, cuando se inyectaba dentro de la vaina axilar. Creemos que solamente con la utilización de esta vía de acceso en la práctica podrá quedar demostrada su eficacia. .

Chronic effect of aspartame versus stevioside on the cerebellar cortex of the adult albino rat: a histological and immunohistochemical study

Sweeteners have evolved rapidly over the last 20 years and are added to a wide variety of food items, drinks, drugs, and hygiene products. Aspartame is the most frequently used artificial sweetener. In contrast, stevioside is a sweet herb that seemed to be a promising natural candidate to replace artificial sweeteners but was found to have hazardous effects on the male reproductive system. The aim of this work was to compare between the histological changes in the cerebellar cortex of adult rats after administration of aspartame and stevioside for 6 months. The reversibility of these changes was also evaluated. A total of 25 albino rats aged 3 months were used in this study. They were divided into five groups comprising five rats each. The first group was the control group. Rats in the second group were given stevioside at a dose of 8.6 mg/day for 6 months. Rats in the third group were given stevioside for 6 months and were then allowed 1 month for recovery. Rats in the fourth group were given aspartame at a dose of 20 mg/day for 6 months. Rats in the fifth group were given aspartame for 6 months and were then allowed 1 month for recovery. Specimens of the cerebellar cortex were processed for H and E and subjected to immunohistochemical staining for glial fibrillary acidic protein [GFAP] and caspase-3 and electron microscopic study. Morphometric and statistical analyses were performed to count the number of Purkinje cells, the number of granular cells, and the number of GFAP and caspase-3 immunostained cells. The present study showed degenerative changes in the Purkinje and granular cell layers in both the aspartame-treated and stevioside-treated groups. This was confirmed by a significant increase in caspase-positive cells and a significant decrease in cell number. Moreover, there was marked increase in the number of astrocytes in areas of degeneration. This was confirmed by a significant increase in GFAP immunostaining. Recovery from stevioside was better than that from aspartame, as evidenced by the normal histological appearance of Purkinje cells and less vacuolated neuropils. This was supported by a significant increase in the number of neurons, significant decrease in caspase-positive cells, and significant decrease in GFAP immunostaining in the recovery group from stevioside compared with the recovery group from aspartame. Cessation of stevioside gives better results and leads to better improvement of the histological picture of the cerebellar cortex compared with cessation of aspartame

Effect of aflatoxin-B1 on rat cerebellar cortex: light and electron microscopic study

Introduction: Aflatoxin contamination of foods is a worldwide problem, especially in developing countries. The effects of aflatoxins on the cerebellum are not well studied

Aim of the study: The aim of the present study was to evaluate the possible neurotoxic effects of aflatoxin B1 on the cerebellar cortex of adult male albino rats

Materials and methods: A total of 30 adult female albino rats were used. They were divided into two groups. Group I [10 animals] was allowed water ad libitum and fed a standard diet [negative control]. Group II [20 animals] was administered 5 ml aflatoxin B1 orally by a gastric tube every week for 8 consecutive weeks. Samples from the cerebella were taken and processed for light and electron microscopic investigation

Results: Light microscopic examination of the cerebellar cortex of aflatoxin-treated animals showed its prominent neurotoxic effect on the Purkinje cell layer, with less effect on the granular and molecular layers. Glial fibrillary acidic protein-positive cells were more abundant in the three cortical layers of treated animals compared with the control animals. Ultrastructural study of the cerebellum of the aflatoxin-treated group showed dilated Golgi complex and accumulation of secondary lysosomes in association with nuclear shrinkage and irregularity within Purkinje cells. Many myelinated nerve fibers and nerve cell processes in the molecular and granular layer belonging to the affected nerve cells showed degenerative changes

Conclusion: It could be concluded according to this study that aflatoxin B1 has a neurotoxic effect on the cerebellar cortex of adult female albino rats

Effect of selenium in ameliorating the effect of induced perinatal hypothyroidism on postnatal rat cerebellar cortex development: a histological and immunohistochemical study

Background: Thyroid hormone plays a key role in the development of the cerebellar cortex. Selenium is a nutritional element with antioxidant and neuroprotective properties

Aim: The aim of this study was to investigate the effect of selenium on the structural impairment of postnatal rat cerebellar cortex development induced by perinatal experimental hypothyroidism

Materials and methods: Pups from 20 pregnant rats were divided into four equal groups: group I: negative control group, group II: methimazole-induced hypothyroid group, group III: selenium-supplemented hypothyroid group, and group IV: selenium-supplemented group [positive control]. Treatment continued from gestational day 14 to postnatal day [P] 14. At P7, P14, and P28, blood samples were collected for assessment of serum thyroid hormone and right cerebellar hemisphere specimens were processed for histological, immunohistochemical, and morphometric procedures

Results: Pups of hypothyroid group showed a retarded postnatal cerebellar cortex development, more apparent at P7 and P14, evidenced by increased thickness of the external granular layer and delayed alignment and differentiation of Purkinje cells in addition to reduced proliferating cell nuclear antigen and increased caspase 3-immunoreactivity. At P28, dark cell degeneration of most Purkinje cells was observed. A significant decrease in the thickness of the molecular and internal granular layers and of the number and surface area of Purkinje cells was observed in all postnatal ages studied. Glial fibrillary acidic protein immunostaining showed increased positive astrocytes with twisting and thickening of their glial fibers. Selenium caused a marked amelioration of most of these structural alterations

Conclusion: Perinatal hypothyroidism impaired postnatal cerebellar cortex development. Selenium should be used as a dietary supplement during pregnancy, particularly in hypothyroid conditions

Ventriculosubgaleal shunt in the management of obstructive hydrocephalus caused by cerebellar infarction

Cerebellar infarction is relatively uncommon. Small infarctions only cause cerebellar manifestations e.g. ataxia and nystagmus and are treated medically. Large cerebellar infarctions, however, can be life threatening. It cause brain stem compression and can obstruct the cerebrospinal fluid pathway causing obstructive hydrocephalus. It has to be treated promptly and may require besides the medical treatment surgical intervention as well. This is mainly in the form of posterior fossa decompression. In this study, we studied the beneficial effect of inserting a temporary ventriculoperitoneal shunt to relieve the supratentorial hydrocephalus in addition to posterior fossa decompression on the morbidity and mortality of patients in comparison to posterior fossa decompression alone. The aim of this study was to evaluate the role of ventriculosubgaleal shunt in cerebellar infarction causing supratentorial ventricular dilatation. This was a retrospective study that included ten patients having extensive cerebellar infarction causing spratentorial hydrocephalus. They were divided into two groups, group [1] was submitted to posterior fossa decompression alone and group [2] was submitted to posterior fossa decompression in addition to temporary ventriculosubgaleal shunt insertion. Group [2] which had posterior fossa decompression in addition to temporary. ventriculosubgaleal shunt hadmuch better results than group [1] which had only posterior fossa decompression. Group [2] had a lower morbidity and mortality and a shorter hospital stay than group [1]. Temporary insertion of ventriculosubgaleal shunt is recommended in patients having extensive cerebellar infarction causing supratentorial hydrocephalus in addition to posterior fossa decompression. It results in a lower morbidity and mortality and a shorter hospital stay

Effects of aluminum on rat cerebellar cortex and the possible protective role of Nigella sativa: a light and electron microscopic study

Aluminum [AL] is toxic to the central nervous system, and Nigella sativa [NS] reduces lipid peroxidation by its antioxidant activity. To investigate the effects of AL treatment on rat cerebellar cortex and the possible protective role of NS. Twenty-five adult male albino rats were divided into five groups: a control group, an NS-treated group, which received NS oil [1ml/kg] orally for 1.5 months, an AL-treated group, which received AL chloride daily [320mg/kg] for 1.5 months, an AL+NS group, which received NS with AL for 1.5 months at the same previous doses, and a withdrawal group, which received AL at the same previous dose for 1.5 months and was left for withdrawal for 1.5 months. Specimens of the cerebellar cortex were processed for light microscopic, electron microscopic, and immunohistochemical study. Morphometric and statistical analysis was carried out. The NS-treated group was very similar to the control group. After the administration of AL, the cerebellum showed a significant reduction in the number of Purkinje cells, which appeared irregular with a darkly stained cytoplasm. The ultrastructure showed Purkinje cells with cytoplasmic vacuolation, dilatation of Golgi cisternae, and mitochondria with dilated cristae. Granule cells showed mitochondria with destroyed cristae. The immune reaction for caspase-3 was intense compared with that of the control group. Administration of NS with AL showed an observable protection against these changes. The withdrawal group showed Purkinje cells that were irregular and darkly stained and their ultrastrucure showed mitochondria with destroyed cristae, but these changes were less marked than those in the AL-treated group. NS may play a protective role against AL-induced cerebellar toxicity in humans

Acute and chronic immobilization stress; morphometric study of Purkinje cells of vermal cerebellar cortex of young male rats

To compare the morphological changes induced by acute and chronic immobilization in vermal cerebellar cortex of young male sprague dawley rats with special reference to Purkinje cells. It was experimental. Department of Anatomy CPSP Reional Centre, Islamabad. Jan 2010 to Dec 2010. A total of 120 young male Sprague Dawley rats were taken and divided equally in two groups [n =60 in each]. Both these groups were divided further into two subgroups [n=30 in each] control acute [CA], immobilized acute [IA], control chronic [CC] and immobilized chronic [IC]. Immobilized acute group IA was kept in restrainer for 24 hours continuously while Immobilized chronic' group 1C was kept in restrainer for 2 hours daily for fourteen days, one rat per restrainer separately Sections stained with Hematoxylin and Eosin were studied under light microscope for observations and data was recorded. Results of experimental acute group were compared with those of experimental chronic'. SSPS version 10 was used for data analysis. Changes in the shape and size of the soma and nucleus of the Purkinje cells were noted. The cells were looking like dried raisins in both experimental groups but these changes were more marked in acute experimental group as compared to controls. The size of the soma and nucleus of the Purkinje cells was reduced in both acute and chronic immobilized stressed groups' however; this reduction in the size of the soma and nucleus of the Purkinje cells was more pronounced in acute stressed group as compared to animals exposed to chronic stress. Total cell count and cell size was significantly decreased in both experimental groups as compared to their controls; however, it was more pronounced in acute stressed group as compared to animals exposed to chronic stress. Immobilization stress may act as a factor causing an imbalance in the metabolic activity of the neurons which can result in neuronal injury The Purkinje neurons were affected more under the effect of acute stress as compared to chronic. The lesser effect in chronic stress is probably due to role of the phenomena of adaptation

Characterization of Membrane Excitability of Purkinje Cells in Vestibulocerebellum Using Patch Clamp Techniques / 대한이비인후과학회지

Cerebellum is known as a center for sensory/motor coordination and memory storage in motor learning. The vestibular nuclei have extensive afferent and efferent connections with posterior cerebellum which can be referred to as vestibulocerebellum. While secondary vestibular afferents are distributed bilaterally in the vestibulocerebellum, primary afferents may directly project to ipsilateral vestibulocerebellum. The Purkinje cells which are the only output neurons from the cerebellar cortex receive vestibular information via parallel and climbing fibers. That information is integrated and encoded in the Purkinje cells and then conveyed into the vestibular nucleus or deep cerebellar nucleus, which permits adaptive guidance of vestibular function by the vestibulocerebellum.

Curcumin Can Prevent the Changes in Cerebellar Structure and Function Induced by Sodium Metabisulfite in Rat

Sulfites are used as anti-microbial and anti-oxidant agents in the food and pharmaceutical industries. Curcumin, a flavonoid, is an Asian spice that shows neuroprotective activities. The current study aimed to stereologically assess the rats' cerebellar cortex and rotarod performance following sulfite exposure and determine the possible neuroprotective potential of curcumin. The rats were divided into five groups: distilled water, olive oil, curcumin (100 mg/kg/day), sodium metabisulfite (25 mg/kg/day), and sodium metabisulfite+curcumin. At 56 days after treatment, rotarod performance was tested, and then the cerebellum was removed for stereological analysis. The study results revealed 31%, 36%, 19% and 24% decrease in the total volume of the cerebellum, cortex, the total number of the Purkinje cells and length of the nerve fibers in the cortex per Purkinje, respectively in the sodium metabisulfite-treated rats compared to the distilled water group (p<0.01). The pre-trained animals on the rotarod apparatus were tested first on the fixed speed rotarod protocol followed by the accelerating rotarod protocol two days later. The results showed a significant decrease in the latency to fall in both test in sulfite-treated rats. The sulfite effects on the structural parameters and rotarod performance were significantly protected by the concomitant curcumin treatment (p<0.001). Sulfite can induce structural and functional changes in the rats' cerebellum and concomitant curcumin prescription plays a neuroprotective role.

Estudio morfométrico comparativo de la corteza cerebelosa humana en dos grupos etarios / Comparative morphometric study of human cerebellar cortex in two age groups

Histológicamente la corteza del cerebelo humano adulto presenta tres capas constitutivas; la capa molecular, la hilera de los cuerpos de las células de Purkinje y la capa granulosa interna. La sustancia cortical del cerebelo de los embriones de mamífero, así como la de los jóvenes, muestran una capa granular externa. Nuestro objetivo es documentar las diferencias morfológicas entre las capas de la corteza cerebelosa adulta y joven. Se realizaron estudios morfométricos microscópicos en 20 cerebelos de autopsias. Los casos se dividieron en dos grupos, adultos y niños menores de 1 año. Se realizaron cortes en parafina, coloreados con hematoxilina y eosina. La corteza del cerebelo adulto presentó diferencias morfológicas con la de los recién nacidos. En el cerebelo adulto presenta tres capas constitutivas, mientras que en el recién nacido presenta una cuarta capa, la granulosa externa...

Histologically, the adult human cerebellar cortex has three constituent layers, the molecular layer, the row of bodies of Purkinje cells and internal granular layer. The cortex of the cerebellum of mammalian embryos, as well as youth, show external granular layer. Our goal is to document morphological differences between the layers of the cerebellar cortex adult and young. Microscopic morphometric studies were performed in 20 cerebellum autopsied. The cases were divided into two groups, adults and children under 1 year. Paraffin sections were performed, stained with hematoxylin and eosin. The cortex of adult cerebellum showed morphological differences of the newborn. In the adult cerebellum has three constituent layers, whereas in the newborn has a fourth layer, the external granular...