Síndrome del ocho y medio secundario a vasculopatía lúpica: presentación de un caso / Eight-and-a-half syndrome secondary to lupus vasculopathy: a case presentation

RESUMEN Introducción: El manejo diagnóstico y terapéutico en los pacientes con lupus eritematoso sistémico que desarrollan una afectación neuropsiquiátrica representa un reto, debido a la heterogeneidad de las formas en que puede presentarse y la ausencia de criterios diagnósticos. Objetivo: Reconocer las formas clínicas de presentación de los síndromes neuroftalmológicos que traducen afectación pontina. Presentación del caso: Hombre de 71 años con antecedente de lupus eritematoso sistémico con afectación neuopsiquiátrica, que de forma aguda desarrolla un cuadro emético en el curso de una emergencia hipertensiva seguido de una parálisis de la mirada horizontal hacia la izquierda, una oftalmoplejía internuclear posterior derecha y una parálisis facial izquierda. En la neuroimagen se constata una afectación multifocal con marcado daño pontino. Conclusiones: Reconocer las formas clínicas de presentación de estos trastornos neuroftalmológicos raros que generalmente se presentan de forma aguda/subaguda permite al neurólogo realizar el diagnóstico topográfico de la lesión a nivel protuberancial con elevada precisión desde la Sala de Urgencias, así como reducir los posibles diagnósticos diferenciales a una etiología vascular, desmielinizante u ocupativa de espacio(AU)

ABSTRACT Introduction: The diagnostic and therapeutic management of patients with systemic lupus erythematosus who develop a neuropsychiatric involvement represents one of the biggest challenges due to the heterogeneity of the ways in which it can occur and the absence of diagnostic criteria. Objective: To recognize the clinical forms of presentation of neurophthalmological syndromes that express pontine involvement. Case presentation: Seventy-one-year-old man with history of systemic lupus erythematosus with neuropsychiatric involvement who acutely develops an emetic episode in the course of a hypertensive emergency followed by a paralysis of the horizontal gaze to the left, a right-sided posterior internuclear ophthalmoplegia and a left facial palsy. In the neuroimaging, a multifocal involvement with marked pontine damage is observed. Conclusions: Recognizing the clinical forms of presentation of these rare neurophthalmological disorders that generally occur in an acute or subacute form allows the neurologist to perform the topographic diagnosis of the lesion at a protuberancial level with high precision from the time when the patient attends the Emergency Department and reduces the possible differential diagnoses to a vascular, demyelinating or occupational etiology of space(AU)

Descripción de cambios en la difusibilidad media en resonancia magnética por lesiones del sistema reticular activador ascendente en pacientes adultos con trauma craneoencefálico y alteración del estado de conciencia / Description of changes in mean diffusivity in magnetic resonance of injuries of the ascending reticular system in patients with traumatic brain injury and impaired consciousness

RESUMEN INTRODUCCIÓN: Los pacientes con trauma craneoencefálico severo pueden tener secuelas neurológicas graves que generan discapacidad de rangos diferentes según la escala de Barthel. La alteración del estado de consciencia es la secuela más grave y es causa de dependencia completa de estos pacientes por la pérdida del autocuidado. La relación entre los hallazgos anormales en las neuroimágenes y los diferentes estados de conciencia ha sido objeto de investigación en los últimos años, con la posibilidad de que existan nuevas opciones con el posproceso de imágenes obtenidas por resonancia magnética nuclear. Este estudio pretende describir las alteraciones en la difusibilidad media haciendo posproceso en la secuencia de DWI en 4 pacientes con trauma craneoencefálico severo y alteración del estado de consciencia, quienes en la fase aguda del trauma fueron estudiados con imágenes convencionales de tomografía y resonancia. MATERIALES Y MÉTODOS: Se describe una serie de 4 casos de pacientes con trauma craneoencefálico severo y alteración del estado de consciencia a quienes se realizó resonancia cerebral simple. Las imágenes fueron sometidas a un posproceso de la secuencia de DWI analizando diferentes regiones por donde transcurren las fibras del sistema reticular activador ascendente (SRAA) (cuerpos restiformes, rafe medio del mesencéfalo, tálamo, regiones subinsulares y lóbulos frontales basales). Igualmente se tomaron valores de difusibilidad en regiones similares, en 5 sujetos sin alteración estructural cerebral tomados como controles. RESULTADOS: Se encontró disminución en la difusibilidad media en las diferentes regiones establecidas en el estudio, que tuvieron diferente localización en cada paciente. Los valores disminuyeron aproximadamente en un 50 % respecto a los del grupo control, observando lesiones en áreas que no fueron identificadas en la interpretación de la imagen cuando fue adquirida durante el trauma. CONCLUSIONES: El posproceso de la secuencia DWI muestra disminución en los valores de difusibilidad media en regiones por donde transcurren las vías del sistema reticular activado ascendente, estos cambios que explican las diferentes alteraciones en el estado de conciencia, no fueron visualizados en las imágenes interpretadas bajo las técnicas convencionales. Se requiere nuevos estudios para establecer las características operativas de la prueba que permitan definir su potencial utilidad dentro de los algoritmos de clasificación inicial de los pacientes con trauma craneoencefálico severo.

SUMMARY INTRODUCTION: Patients with severe traumatic brain injury may have severe neurological sequelae that generate disability of different ranges, according to the Barthel scale. The consciousness impairment is the most serious sequela and is a cause of complete dependence of these patients, due to the loss of self-care. The relationship between abnormal findings in neuroimaging and different states of consciousness has been the subject of research in recent years, with the possibility of new options with the post-processing of magnetic resonance imaging (MRI). This study aims to describe the alterations in the mean diffusivity by post-processing of the diffusion weighted imaging (DWI) sequence in 4 patients with severe traumatic brain injury and impairment of consciousness, who were studied with computed tomography (CT) and MRI in the acute phase of the trauma. MATERIALS AND METHODS: We describe a series of 4 cases of patients with severe traumatic brain injury and impaired consciousness in whom a non-enhanced brain MRI was performed. The DWI sequence images were post-processed, analyzing different regions through which the fibers of the Ascending Reticular Activating System (ARAS) (including restiform bodies, midbrain, thalamus, sub-insular regions and basal frontal lobes) pass. Likewise, diffusivity values were taken in similar regions, in 5 subjects without any structural brain abnormality, who were taken as controls. RESULTS: There was a decrease in mean diffusivity in the different regions established in the study, which had different locations in each patient. Values decreased approximately 50 percent from values in normal patients. After post-processing, some lesions were observed in areas that were not identified in the initial MRI interpretation during the trauma. CONCLUSIONS: The post-processing of the DWI sequence shows a decrease in the mean diffusivity values in regions where the ARAS pathways pass through. These changes explaining the different alterations in consciousness were not visualized in the images interpreted under conventional MRI techniques. New studies are required to establish the operative characteristics of this test, that allow to define its potential utility within the algorithms of initial classification of patients with severe traumatic brain injury.

Whole-Brain Mapping of Direct Inputs to and Axonal Projections from GABAergic Neurons in the Parafacial Zone / 神经科学通报·英文版

The GABAergic neurons in the parafacial zone (PZ) play an important role in sleep-wake regulation and have been identified as part of a sleep-promoting center in the brainstem, but the long-range connections mediating this function remain poorly characterized. Here, we performed whole-brain mapping of both the inputs and outputs of the GABAergic neurons in the PZ of the mouse brain. We used the modified rabies virus EnvA-ΔG-DsRed combined with a Cre/loxP gene-expression strategy to map the direct monosynaptic inputs to the GABAergic neurons in the PZ, and found that they receive inputs mainly from the hypothalamic area, zona incerta, and parasubthalamic nucleus in the hypothalamus; the substantia nigra, pars reticulata and deep mesencephalic nucleus in the midbrain; and the intermediate reticular nucleus and medial vestibular nucleus (parvocellular part) in the pons and medulla. We also mapped the axonal projections of the PZ GABAergic neurons with adeno-associated virus, and defined the reciprocal connections of the PZ GABAergic neurons with their input and output nuclei. The newly-found inputs and outputs of the PZ were also listed compared with the literature. This cell-type-specific neuronal whole-brain mapping of the PZ GABAergic neurons may reveal the circuits underlying various functions such as sleep-wake regulation.

Modelo in vitro para el estudio del papel de la unión mesopontina en la generación del sueño de movimientos oculares rápidos y la vigilia / In vitro model for the study of the role of the mesopontine region in rapid eye movement (REM) sleep and wakefulness / Modelo in vitro para o estudo do papel da união mesopontina na geração de sono de movimentos oculares rápidos e da vigília

El estudio de las estrategias neurales para la organización del comportamiento en vertebrados constituye un desafío mayor para la Neurociencia. El avance del conocimiento en este campo depende de manera crítica de la utilización de modelos experimentales adecuados que admitan múltiples niveles de análisis (p.ej: comportamental, circuital, celular, sináptico, molecular) y abordajes multitécnicos. Nos propusimos analizar in vitro una red neural de la unión mesopontina del tronco encefálico críticamente implicada en el control del sueño de movimientos oculares rápidos (S-REM). Pese al cúmulo de evidencias que apoyan el papel desempeñado por esta red en relación al S-REM, los mecanismos celulares y sinápticos que subyacen a este control son poco conocidos y continúan siendo objeto de intensa investigación. Para avanzar en el conocimiento de estos mecanismos, se llevó a cabo la caracterización morfológica y funcional de una rodaja de tronco encefálico de la rata, en la que las estructuras críticas para el control del S-REM, i.e.: núcleos tegmentales laterodorsal y pedúnculopontino, y su proyección al núcleo reticular pontis oralis (PnO), están presentes y son operativas. La inclusión del núcleo motor del trigémino en la rodaja permitió detectar cambios de la excitabilidad de las motoneuronas ante manipulaciones farmacológicas del PnO, representativos de los cambios del tono muscular asociados a maniobras similares realizadas in vivo. La utilización de este modelo in vitro de S-REM, permitirá aportar a la dilucidación de las estrategias neurales que operan en niveles intermedios de organización del SN en mamíferos para la generación y regulación de un estado comportamental.

The study of the neural basis of behavior is a major challenge in Neuroscience. Advancing our knowledge in this field depends, critically, on the use of experimental paradigms that provide multiple levels of analysis, as well as powerful techniques. We have selected, as a model of a neural plan that organizes a complex behavior, a neural network located in the mesopontine junction. This region is thought to be both necessary and sufficient for the generation of rapid eye movement (REM) sleep, although the cellular and synaptic mechanisms involved in the control of this behavioral state at the mesopontine level are still under debate and remain poorly understood. As part of a long term effort to gain insight into these mechanisms, we carried out the morphological and functional characterization of a slice preparation of rat brainstem and we demonstrate that critical structures for the control of REM sleep - the laterodorsal and pedunculopontine tegmental nuclei and their projection to the oral part of the pontine reticular nucleus (PnO) - are present and are operational. The presence of the trigeminal motor nucleus in the slice sought to include in the experimental model a structure capable of expressing changes of the excitability of the motorneurons caused by pharmacological manipulations of the PnO, representative of changes of muscle tone associated with similar maneuvers performed in vivo. The use of this in vitro model of REM sleep will provide critical information to elucidate neural strategies that operate at intermediate levels of central nervous system organization in mammals to control behavioral states.

O estudo de estratégias neurais para a organização do comportamento em vertebrados constitui um desafio maior para a Neurociencia. O avanço do conhecimento nessa área depende criticamente da utilização de modelos experimentais adequados que suportem múltiplos níveis de análise (por exemplo: comportamental, circuital, celular, sináptico e molecular) e abordagens por múltiplas técnicas. Decidiu-se analisar in vitro uma rede neural da união mesopontina do tronco encefálico criticamente envolvida no controle do sono de movimentos oculares rápidos (S-REM). Apesar da riqueza de provas que sustentam o papel desta rede em relação ao S-REM, os mecanismos celulares e sinápticos subjacentes a este controle são pouco conhecidos e permanecem sob intensa investigação. Para avançar no conhecimento desses mecanismos, caracterizou-se morfológica e funcionalmente uma fatia de tronco encefálico de rato, na qual as estruturas críticas para o controle do S-REM, i.e.: núcleos tegmentais laterodorsal e pedunculopontino, e sua projeção para o núcleo reticular pontis oralis (PnO) estão presentes e operantes. A inclusão do núcleo motor do trigêmeo na fatia permitiu detectar mudanças da excitabilidade das motoneuronas provocadas por manipulações farmacológicas do PnO, representativas das alterações do tônus muscular associados com operações semelhantes quando realizados in vivo. A utlização deste modelo in vitro de S-REM permitirá contribuir para a elucidação de estratégias neurais que operam em níveis intermedios de organização do SN de mamíferos para a geração e regulação de um estado comportamental.

Functional Neuroanatomy of Brain Stem

The brain stem consists of medulla oblongta, pons and midbrain. It is sited in posterior cranial fossa. It contains numerous intrinsic neuron cell bodies and their processes, some of which are the brain stem homologues of spinal neuronal groups. These include the sites of termination and cells of origin of axons that enter or leave the brain stem through the cranial nerves. Cranial nerves provide sensory, motor and autonomic innervations of structures that are mostly in the head and neck. The reticular formation is an extensive network of neurons that extends throughout the length of brain stem and is continuous rostrally to diencephalon and caudally to its spinal counterpart. Clinically, damage to the brain stem is often devastating and life threatening. This is because it is a structurally and functionally compact region. Therefore, it is important to build basic knowledge about neuroanatomy of brain stem.

Medial pontine reticular formation: A potential anesthetic target / 第二军医大学学报

Medial pontine reticular formation (mPRF),an important part of brainstem reticular formation, has drawn great attention from anesthesiologists due to its close relation with not only consciousness, but also analgesia, muscle relaxation and autonomic reflex. Progress in related research may provide evidence for understanding the mechanism of general anesthesia; meanwhile,it may serve as an effective anesthesia target site, which may contribute to improvement in anesthetic effect and reduction of complications.

Delayed-Onset Continuous Bruxism with Olivary Hypertrophy After Top of the Basilar Syndrome

Delayed-onset continuous bruxism due to brain stem infarction has not yet been reported. A 49-year old man presented with quadriplegia and ophthalmoplegia. Brain MRI showed acute infarction in the bilateral midbrain, right thalamus and the superior cerebellum. One month later, the patient developed bruxism which persisted during sleep. A palatal myoclonus was not observed. Follow up MRI taken 4 months later showed bilateral olivary hypertrophy. We suggest that the patient's bruxism may be related to the olivary hypertrophy. The bruxism generator may be located in the pontine-reticular-formation (PRF). Bilateral large midbrain lesions interrupting the cortical inhibition may have produced bilateral olivary hypertrophy, which could stimulate the PRF, producing continuous bruxism.

A Case of Bilateral Horizontal Gaze Palsy due to Pontine Hemorrhage

PURPOSE: To report a case of bilateral horizontal gaze palsy associated with pontine hemorrhage. METHODS: A 51-year-old man developed a sudden decrease in consciousness. Computed tomography reveal a pontine hemorrhage and infarctions of both basal ganglia. The mentality was recovered after conservative treatment, but he complained of difficulty in moving his eyes. We performed ophthalmic and radiologic evaluations to confirm a diagnosis of bilateral horizontal gaze palsy and to reveal the condition. RESULTS: On ophthalmic examination, his eye showed complete bilateral horizontal gaze palsy, but convergence and vertical eye movements were normal. Radiologic evaluation revealed a pontine hemorrhage, and the hemorrhagic area was consistent the bilateral paramedian pontine reticular formation (PPRF).

Transplantation of schwann’s cells transfected by brain derived neurotrophin factor gene into electrical reticular lesion of the brain stem in rats / 中华创伤杂志

Objective To investigate the effect of brain derived neurotrophin factor (BDNF) transfected with cationic liposome in protecting nerve tissue and promoting regeneration of the myelin sheath. Methods Wistar rat Schwanns cells (SWCs) were cultured in vitro. The recombinant cationic liposomes mediated PCDNA 3 BDNF was transplanted into SWCs and then into electrical reticular lesion of the brain stem (Group Ⅰ). At the same time, pure cell transplantation group (Group Ⅱ), empty transfected vector cell transplantation (Group Ⅲ) and normal saline injection group (Group Ⅳ) were set. The concentration of BDNF in the brain stem was measured by ELISA, the survival of myelinated basic protein (MBP) and SWCs in the brain stem by immunohistochemistry and the regeneration of the myelin sheath by the transmission electron microscope (TEM). Results One week after transplantation, the concentration of BDNF in the brain stem in the Group Ⅰ was much higher than that in other three groups ( P

Neuro-Behcet's Disease Presenting with Foville Syndrome : A Case Report

A Foville syndrome is rare. A 46-year-old man with a 3-year history of Behcet's disease presented with a right facial palsy and a limitation in the rightward movements of the eyes. On neurologic examination, there was no movement of eyes in the right hemifield during all kinds of eye movements, including saccade, smooth pursuit, vestibulo-ocular reflex, and optokinetic nystagmus. However, all the eye movements were normal in the left hemifiled except for slowed saccades toward the right. Additional features were right infranuclear facial paresis and extensor plantar response on left side. Brain MRI revealed high signal intensity lesions in the right pons both in the dorsal tegmentum and in the basis. Neurological signs resolved gradually with steroid treatment. Different clinical features between abducens nucleus syndrome and paramedian pontine reticular formation syndrome are briefly discussed. To the authors' knowledge, this is the first case report of a Foville syndrome caused by neuro-Behcet's disease.

Analgesic effect of adenosine A_1 receptor agonist administered into the brainstem medial pontine reticular formation in rats / 中华麻醉学杂志

Objective To investigate the analgesic effect of adenosine A1 receptor agonist R( - )-N6-(2-phenylisopropyl)-adenosine (R-PIA) administered into the brainstem medial pontine reticular formation (mPRF) and the underlying mechanism. Methods Sixty male SD rats aged 8-10 weeks weighing 250-300 g were used in this study. The animals were anesthetized with intraperitoneal 10% chloral hydrate 300 mg?kg-1 .A 24-gauge stainless steel cannula was inserted into mPRF on one side using a stereotaxic apparatus. One week after operation the animals were randomly divided into 12 groups ( n=5 each) : groupⅠcontrol; groupⅡR-PIA 0.5?g; groupⅢR-PIA 1.0?g; groupⅣR-PIA 2.0?g; groupⅤtheophylline (an adenosine receptor antagonist) 5.0?g; groupⅥ8-cyclopentyl-1 ,3-dipropylxanthine (DPCPX, an adenosine A, receptor antagonist) 1.0?g; groupⅦglibenclamide (an ATP-sensitive K+ channel blocker) 5.0?g; groupⅧ4-aminopyridine (4-AP, a voltage dependent K+-channel blocker) 5.0?g; groupⅨtheophylline 5.0?g + R-PIA 2.0?g; groupⅩDPCPX 1.0?g + R-PIA 2.0?g; groupⅪglibenclamide 5.0?g + R-PIA 2.0?g and groupⅫ4-AP 5.0?g + R-PIA 2.0?g. All the drugs were injected into mPRF in 0.3?l of normal saline. In groupⅨ-ⅫR-PIA 2.0?g was administered 15 min after pretreatment with theophylline, DPCPX, glibenclamide or 4-AP. Analgesia was determined using the tailflick latency (TFL) (the time between the onset of the radiant heat stimulus and voluntary tail withdrawal) at 5, 15, 30, 45, 60 and 90 min after R-PIA injection into mPRF. The pain threshold was expressed as percentage of the maximal possible effect ( MPE) : MPE = (TFL after drug - baseline TFL)/( 10.0 -baseline TFL)?100% .Results R-PIA 0.5-2.0?g injected into mPRF produced significant analgesia in a dose-dependent manner. Pretreatment with theophylline or DPCPX completely reversed the analgesic effect of R-PIA while pretreatment with glibenclamide or 4-AP only partially reversed the analgesic effect of R-PIA.Conclusion R-PIA administered into mPRF produces analgesia through activation of both ATP-sensitive and voltage-dependent K+ -channel in mPRF.

The Characteristic and Origin of Motor Evoked Potential in Rats

Motor evoked potential(MEP) produced by cortical surface or transcranial stimulation has evolved as a new clinical and experimental tool to monitor the integrity of motor pathways and to map motor cortex. Clinical assessment of motor system using MEP has further advanced with recent development of the magnetic stimulator. The primary concept using MEPs for test of motor pathways was based on the assumption that pyramidal neurons in the motor cortex are activated by electrical stimulation applied on the cerebral cortex and synchronized compound action potentials are conducted mainly along the corticospinal tracts in the spinal cord. However,recent studies indicated that the origins of the Meps in non primates may differ from those previously believed. In order to use MEPs as a clinical or experimental tool, it is essential to clarify the origin of MEPs. Therefore, goals of this study were : (1) to investigate the origin of MEPs, and (2) to design the most reliable but simple method to evoke and monitor MEPs. In a total of fifteen rats, MEPs were produced by cortex to cortex stimulation and were monitored using a pair of epidural electrodes. Using varying stimulus intensities, the amplitudes and latencies of MEPs were statistically analyzed. The latencies and amplitudes of the MEPs in these animals showed surprisingly large standard deviations, which were partially resulted in these animals showed surprisingly large standard deviations, which were partially resulted from convergence of neighboring waves during high stimulation intensities. Wave forms of MEPs were also varied greatly depending on the position of recording electordes. At low stimulus intensities, most consisten MEPs were obtained when the stimulating electrodes were placed on the hard palate and the temporal muscle, not on the motor cortex. This observation indicates that the primary source of MEPs is not the motor cortex in the rat. When the potentials generated by direct stimulation of motor cortex and those generated by reticular nuclei were monitored epidurally in the same preparation using the same electrodes, these potentials generated by different sources actually identical in their latencies and wave forms. However, the threshold stimulus intensities evoking these potentials were quite different in the two metholds. The threshold was much lower to evoke potentails by reticular nuclei stimulation. It suggests that MEPs are geneated by the reticular nuclei or brain structure located in the brain stem. The observation that the motor cortex play no major roles in generating MEPs was confirmed by sequential sections of neural axis from the motor cortex to brain stem in three rats. All these findings suggested that neither direct motor cortex stimulation not transcranial stimulation did evoke MEPs originating from the motor cortex in rat. These stimulating methods activate reticular nuclei by stimulus current spread to the brain stem. Since the reticular formation plays an important role in motor function in rats, MEP originated from reticular nucleus can be an important testing of the motor function in rats. Moreover, transcranial stimulation of the brain is technically easy. This technique producing MEPs originated from reticular nucleus can be useful to monitor the integrity of motor pathways.

The Intraspinal Pathways Conducting Motor Evoked Potentials in Rats

Recently, motor evoked potential(MEP) using cortical surface of transcranial stimulation have been used to monitor the integrity of motor pathways and map motor cortex in human and animal. The primary concept using motor evoked potentials(MEPs) for test of motor pathways was based on the assumtion that pyramidal neurons in the motor cortex are activated by electrical stimulation applied on the cerebral cortex and synchronized compound action potentials are conducted mainly along the corticospinal tracts in the spinal cord. However, the origins and the descending pathways of these MEPs in small animals may be different from those of potentials evoked by intracortical microstimulation because of current spread. Our previous study revealed that the origns of the MEPs in rats differed from those previously believed and may be reticular nuclei. To further clarify those results and localize the intraspinal pathways conduction MEPs, consecutive vertical and/or horizontal sections of the spinal cord were performed at T9 cord level in twelve rats. MEPs were recorded at T2/3 and L2/3 before and after each section and sequential alterations of MEPs were observed. In six rats, the stimulation was alternated between the right and left cortex and the lateralities of conduction pathways were compared. All six cases showed no differences of MEPs and pattern of wave abolition after each section between right and left brain stimulation. The alteration of MEPs after each consecutive section was categorized by analyzing latency shift, amplitude change, and disappearance of waves. We divided a cross section of T9 spinal cord into forty-six squares. If one of the categorized changes occurrd after cutting an area, the appropriate score was given for the area since more change of waves meant more significant contribution of the cut area to conduction of MEPs. The score of twelev rats were summed in each forty-six spots and map showing the distribution of MEPs was constructed. The map revealed that MEPs were conducted along the wide area of ventral and lateral funiculus of the spinal cord but mainly along the medial portion of the ventral funiculus of the spinal cord but mainly along the medial portion of the ventral funiculus and ventral portion of the larteral funiculus through which reticulospinal and vestibulospinal tracts pass. No conduction of MEPs along the corticospinal tracts was confirmed. This finding supports the result of our previous study. However, this extrapyramidal MEP conducted along ventral spinal cord in addition to somatosensory evoked potential(SSEP) which is conducted along posterior funiculus can be useful to monitor the integrity of the whole spinal cord. Moreover, the extrapyramidal MEP can be more useful than pyramidal MEP in rats because the reticular formation plays a more important role in motor function and pyramidal tract is located in posterior funiculus.

THE SPINAL PROJECTION FROM THE GIGANTIC NEURONS IN THE RETICULAR FORMATION OF THE MIDBRAIN IN THE RABBIT——HRP AND WGA-HRP TECHNIQUES / 解剖学报

It was discovered that there were a group of gigantic neurons scattering in the tegmentum dorsolateral to the oral half of the red nucleus in the midbrain of the rabbit. The form and size of these neurons were similar to the gigantic cells in the gigantocellular reticular nucleus of the medulla oblongata. After injecting HRP or WGA-HRP in the cervical, thoracic or lumbar spinal segment of the rabbit, more than a half of these gigantic cells were labeled. The labeled cells were most crowded at the oral end level of the red nucleus. There were also labeled terminals near the labeld cells in the reticular formation of the midbrain. It is evidently that there are reciprocal connections between the spinal cord and the reticular formation of the midbrain in the rabbit.

OBSERVATION ON THE ARTERIES OF THE HUMAN MEDULLA OBLONGATA / 解剖学报

The origin, distribution, anastomoses and variations of the arteries of medulla oblongata were observed on 110 Chinese adult brains. The internal arteries and their territories were observed on 20 brains by artereography and clearing method (Spalteholz's technic). The results were as follows: The arteries of medulla oblongata could be divided into four groups according to their distribution. The arteries of the anteromedian and anterolateral groups arose from the anterior spinal artery, and also from the vertebral artery and basilar artery. The arteries of the lateral group contained a series of small arterial rami, which arose from the vertebral artery, posterior inferior cerebellar artery, anterior inferior cerebellar artery and basilar artery. The arteries of the posterior group arose from the posterior spinal artery and posterior inferior cerebellar artery. The arteries of each group branched and penetrated into the medulla, they ramify into fine branches, and the capillary network was formed. The internal anteromedian arteries supplied the hypoglossal nucleus, medial lemniseus etc. The internal anterolateral arteries supplied chiefly pyramidal tract. The internal posterior arteries supplied the gracile and cuneate nuclei. The internal lateral arteries supplied the rest of the areas which include reticular formation, dorsal nucleus of the vagus nerve etc.. The arterial supply of the medullary lateral area and the endartery were discussed.