RESUMO

The cerebellum is a structure of the central nervous system which has been previously studied with different techniques and animal models and even humans, so it is associated with multiple functions such as cognition, memory, emotional processing, balance, control of movement, among others. Its relationship with sensory systems has already been explored, however, the role it plays in olfactory processing in the cerebellum is unclear. Several hypotheses have been proposed from work done in humans and animal models with neuroimaging and immunohistochemical techniques. Everything seems to indicate that the cerebellar function is of vital importance for the olfactory perception, being able to be controlling not only the olfactory aspect, but also the olfactory processing. In this study we analyzed the multiunit activity in the granular layer of the cerebellar vermis during olfactory stimulation: a session being sexually naive and during four sessions of sexual behavior learning. The amplitude was compared between male naive and sexual experts, as well as between olfactory stimuli. The amplitude of the sexually experienced rats showed the highest values compared to naive ones. Odor of receptive female causes the greatest amplitudes, however, in the control group the amplitude increased when they were sexually experts. The motor, sensory and associative learning generated by the acquisition of sexual experience modifies the activation pattern in the cerebellum by presenting neutral odors or associated with a reward.

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RESUMO

We report two cases of a rare pathology of the fetal cerebellum, rhomboencephalosynapsis, a defect characterized by the partial or complete absence of the cerebellar vermis, which is currently associated with severe ventriculomegaly due to defects in the formation of the cerebral aqueduct. These are the first cases reported in Peru

Reportamos dos casos de una patología rara del cerebelo fetal, la romboencefalosinapsis, defecto caracterizado por la ausencia parcial o completa del vermis cerebeloso, frecuentemente asociada a ventriculomegalia severa por defectos en la formación del acueducto de Silvio. Estos constituyen los primeros casos reportados en Perú.

RESUMO

The neural histaminergic system innervates the cerebellum, with a high density of fibers in the vermis and flocculus. The cerebellum participates in motor functions, but the role of the histaminergic system in this function is unclear. In the present study, we investigated the effects of intracerebellar histamine injections and H1, H2 and H3 receptor antagonist injections (chlorpheniramine, ranitidine, and thioperamide, respectively) and H4 receptor agonist (VUF-8430) on locomotor and exploratory behaviors in mice. The cerebellar vermis of male mice was implanted with guide cannula. After three days of recovery,the animals received microinjections of saline or histamine (experiment1), saline or chlorpheniramine (experiment 2), saline or ranitidine(experiment 3), saline or thioperamide (experiment 4), and saline or VUF-8430 (experiment 5) in different concentrations. Five minutes postinjection,the open field test was performed. The data were analyzed using one-way ANOVA and Duncan's post hoc test. The microinjections of histamine, ranitidine or thioperamide did not lead any behavioral effects at the used doses. In contrast, animals that received chlorpheniramine at the highest dose (0.16 nmol) and VUF-8430 at the highest dose (1.48 nmol)were more active in the open field apparatus, with an increase in the number of crossed quadrants, number of rearings and time spent in the central area of the arena, suggesting that chlorpheniramine and VUF-8430 modulates locomotor and exploratory behaviors in mice.

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RESUMO

El cerebelo proviene del latín "pequeño cerebro", es aproximadamente una décima parte del cerebro en tamaño y peso, se encuentra en la fosa craneal posterior. está conectado directamente o indirectamente a una variedad de estructuras, incluyendo el tronco cerebral, la columna vertebral, las regiones corticales y subcorticales. El cerebelo contiene casi el 80 % del total de las neuronas del cerebro y se compone de formas diferenciadas de unidades neuronales, cada una compartiendo microcircuitos cerebelosos básicos. El cerebelo está formado por dos hemisferios laterales y una porción media o vermis . El cerebelo tiene varias funciones: coordinar los movimientos voluntarios especializados al influir en la actividad muscular y controlar el equilibrio, el tono muscular a través de conexiones con el sistema vestibular, la médula espinal y sus neuronas motoras alfa. Dentro de la corteza del cerebelo existe una organización somatotópica de las partes del cuerpo. El cerebelo es una pieza clave para el procesamiento de la información y participa en numerosas actividades motoras y no motoras, gracias a las características anatómicas de sus circuitos, las enormes capacidades de análisis y la alta conectividad con otras áreas del cerebro, puede verse afectado por diferentes factores como: anormalidades en el desarrollo embrionario, tóxicos, enfermedades autoinmunes, inflamatorias, vasculares y metabólicas, infecciones, tumores primarios y secundarios, traumas, iatrogénicos, enfermedades genéticas, esporádicas, dando origen a signos y síntomas que causan un síndrome cerebeloso de acuerdo al área anatómica comprometida. En la literatura científica no hay reportes de casos de síndrome cerebeloso por mesalamina (mesalazina). A continuación presentamos el primer caso.

Cerebellum is Latin for "little brain" is about a tenth of the brain in size and weight, is in the posterior cranial fossa. It connects directly or indirectly to a variety of structures, including brainstem, spinal cord, cortical and subcortical regions. The cerebellum contains almost 80% of all neurons in the brain and consists of different forms of neuronal units, each sharing basic cerebellar microcircuits. The cerebellum is formed by two lateral hemispheres and vermis or a middle portion . The cerebellum has several functions: coordinate movements specialized volunteers to influence muscle activity and control the balance, muscle tone through connections with the vestibular system, the spinal cord and alpha motor neurons. Within the cerebellar cortex somatotopic organization exists a body part. The cerebellum is a key to information processing and participates in numerous motor and non-motor activities, thanks to the anatomical characteristics of its routes, huge analysis capabilities and high connectivity with other brain areas, can be affected by different factors such as abnormalities in embryonic development, toxic, autoimmune, inflammatory, vascular and metabolic, infections, primary and secondary tumors, trauma, iatrogenic, genetic diseases, sporadic, giving rise to signs and symptoms that cause cerebellar syndrome according to compromised anatomical area. In the scientific literature no reported cases of cerebellar syndrome mesalamina (mesalazina), we report the first case.

RESUMO

A 2-day-old Mangalarga Marchador colt was presented with clinical signs of severe mental depression, unable to stand, and lacking a suckling reflex. Despite intensive medical care, there was no improvement and the colt died 30 hours later. Gross lesions were characterized by aplasia of the cerebellar vermis, cystic dilatation of the fourth ventricle, communicant hydrocephalus involving all ventricles and villous hyperplasia of the choroid plexus in the fourth ventricle. The cerebral parenchyma adjacent to lateral ventricles was markedly reduced. In addition, there was aspiration pneumonia. Aplasia of the cerebellar vermis and cystic dilatation of the fourth ventricle could be compared to the Dandy-Walker-syndrome (DWS). Nevertheless, congenital cerebellar anomalies combined with villous hyperplasia of the choroid plexus in the fourth ventricle and hydrocephalus are describing for the first time in animals, alerting clinicians and pathologists for future investigations about the incidence and etiology of the condition.

Assuntos

RESUMO

A 2-day-old Mangalarga Marchador colt was presented with clinical signs of severe mental depression, unable to stand, and lacking a suckling reflex. Despite intensive medical care, there was no improvement and the colt died 30 hours later. Gross lesions were characterized by aplasia of the cerebellar vermis, cystic dilatation of the fourth ventricle, communicant hydrocephalus involving all ventricles and villous hyperplasia of the choroid plexus in the fourth ventricle. The cerebral parenchyma adjacent to lateral ventricles was markedly reduced. In addition, there was aspiration pneumonia. Aplasia of the cerebellar vermis and cystic dilatation of the fourth ventricle could be compared to the Dandy-Walker-syndrome (DWS). Nevertheless, congenital cerebellar anomalies combined with villous hyperplasia of the choroid plexus in the fourth ventricle and hydrocephalus are describing for the first time in animals, alerting clinicians and pathologists for future investigations about the incidence and etiology of the condition.(AU)

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RESUMO

This study investigated the effects of histamine H1 or H2 receptor antagonists on emotional memory consolidation in mice submitted to the elevated plus maze (EPM). The cerebellar vermis of male mice (Swiss albino) was implanted using a cannula guide. Three days after recovery, behavioral tests were performed in the EPM on 2 consecutive days (T1 and T2). Immediately after exposure to the EPM (T1), animals received a microinjection of saline (SAL) or the H1 antagonist chlorpheniramine (CPA; 0.016, 0.052, or 0.16 nmol/0.1 µL) in Experiment 1, and SAL or the H2 antagonist ranitidine (RA; 0.57, 2.85, or 5.7 nmol/0.1 µL) in Experiment 2. Twenty-four hours later, mice were reexposed to the EPM (T2) under the same experimental conditions but they did not receive any injection. Data were analyzed using one-way ANOVA and the Duncan test. In Experiment 1, mice microinjected with SAL and with CPA entered the open arms less often (%OAE) and spent less time in the open arms (%OAT) in T2, and there was no difference among groups. The results of Experiment 2 demonstrated that the values of %OAE and %OAT in T2 were lower compared to T1 for the groups that were microinjected with SAL and 2.85 nmol/0.1 µL RA. However, when animals were microinjected with 5.7 nmol/0.1 µL RA, they did not show a reduction in %OAE and %OAT. These results demonstrate that CPA did not affect behavior at the doses used in this study, while 5.7 nmol/0.1 µL RA induced impairment of memory consolidation in the EPM.

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