Nitric oxide is synthesized by neurons containing the nitric oxide synthase (NOS), and the nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) is a selective histochemical marker for the brain. Although, many reports have been published describing in detail the distribution of NADPH-d and tyrosine hydroxylase (TH), little information is available on possible morphological changes of NADPH-d and TH containing neurons during aging of the brain stem. Therefore, in this study, we assessed the effects of aging on the somal area and staining intensity of NADPH-d-positive and TH-immunoreactive (TH-IR) neurons in rat brain stem. In previous studies, enzyme activities of nitric oxide synthase (NOS) and NADPH-d were shown to be in an almost perfect correlation in the brain. Therefore, we evaluated the change of NADPH-d-positive neurons using a microdensitometrical method as a way of measuring changes in NOS activity. By using a double-labelling technique, we have shown that these two enzymes are located in separate neurons in most brain stem nuclei. In the aged group, the size of NADPH-d-positive neurons was not significantly changed in most nuclei of the brain stem compared to the control group. Staining intensity of NADPH-d-positive neurons was significantly changed in periaqueductal gray, superior colliculus and inferior colliculus in the aged group. In the aged rats, the size of TH-IR neurons was significantly changed in locus ceruleus and lateral paragigantocellular nucleus. Staining intensity of TH-IR neurons was significantly decreased in principal trigeminal nucleus, locus ceruleus and lateral paragigantocellular nucleus of the aged group. These results demonstrate that the NADPH-d-positive and TH-IR neurons are differently influenced by aging than the control group in the brain stem of rats. Difference in the changes of NADPH-d-positive neurons in brain stem nuclei suggest that neuronal NOS is regulated by different mechanims in the regions of the brain stem during aging.
Aging* ; Animals ; Brain Stem* ; Brain* ; Inferior Colliculi ; Locus Coeruleus ; NAD ; Neurons* ; Nitric Oxide ; Nitric Oxide Synthase ; Periaqueductal Gray ; Rats* ; Superior Colliculi ; Trigeminal Nuclei ; Tyrosine 3-Monooxygenase ; Tyrosine*

Computerized tomography has been proven to be of particular value in patients with head trauma. Neverthless, primary traumatic brainstem lesions are not always revealing even by the advent of brain CT. In two cases of head trauma, we identified midbrain hemorrhage by CT scan. One of them was hemorrhage in the quadrigeminal plate, the quadrigeminal cistern, and the vermis; the other small round isolated hemorrhage in the quadrigeminal plate. They were well correlated with the clinical findings. Those two patients got well with conservative treatment.
Brain ; Brain Stem* ; Craniocerebral Trauma ; Hemorrhage ; Humans ; Mesencephalon ; Tectum Mesencephali ; Tomography, X-Ray Computed

CEREBELLOPONTINE ANGLE CEREBELLUM METENCEPHALON RHOMBENCEPHALON BRAIN STEM BRAIN CENTRAL NERVOUS SYSTEM NERVOUS SYSTEM NEOPLASMS

The outcome and the rate of rebleeding of brainstem cavernous malformationss were analyzed following conservative treatment, microsurgical excision and Gamma Knife radiosurgery (GKS). We especially concentrated on the role of radiosurgery. We treated 39 patients with brainstem cavernous malformations using conservative treatment, microsurgical removal or GKS from April 1993 to November 2003. Follow up duration was 7 to 132 months (mean 45.8, median 30.6). The lesion location included pons, midbrain, medulla oblongata and cerebellarpeduncle. Conservative management was performed in 14 patients, GKS in 18 patients and microsurgical removal in 7 patients. The annual rate of rebleeding was 22.2% in conservative group and 22.7% in GKS group. Good and moderate outcome were obtained in 70% of conservative group, 75% of GKS group and 85.6% of surgical group. Overall mortality rate was 5.1%. Microsurgical excision tended to be resulted in good outcome. GKS and conservative managements were accompanied by a risk of recurrent bleeding, even death. There was no statistical difference in outcome and the rate of rebleeding between conservatively managed group and GKS treated group.
Brain Stem* ; Follow-Up Studies ; Hemorrhage ; Humans ; Medulla Oblongata ; Mesencephalon ; Mortality ; Pons ; Radiosurgery

PURPOSE: To describe MRI findings of multiple sclerosis involving the brainstem. MATERIALS AND METHODS: Among 35 cases of clinically definite multiple sclerosis, the authors retrospectively analysed 20 in which the brainstem was involved. MR images were analysed with regard to involvement sites in the brainstem or other locations, signal intensity, multiplicity, shape, enhancement pattern, and contiguity of brainstem lesions with cisternal or ventricular CSF space. RESULTS: The brainstem was the only site of involvement in five cases (25%), while simultaneous involvement of the brainstem and other sites was observed in 15 cases (75%). No case involved only the midbrain or medulla oblongata, and simultaneous involvement of the midbrain, pons and medulla oblongata was noted in 12 cases (60%). The most frequently involved region of the brainstem was the medulla oblongata (n=18; 90%), followed by the pons (n=17; 85%) and the midbrain (n=16; 80%). Compared with normal white matter, brainstem lesions showed low signal intensity on T1 weighted images, and high signal intensity on T2 weighted, proton density weighted, and FLAIR images. In 17 cases (85%), multiple intensity was observed, and the shape of lesions varied: oval, round, elliptical, patchy, crescentic, confluent or amorphous areas were seen on axial MR images, and in 14 cases (82%), coronal or sagittal scanning showed that lesions were long and tubular. Contiguity between brainstem lesions and cisternal or ventricular CSF space was seen in all cases (100%) involving midbrain (16/16) and medulla oblongata (18/18) and in 15 of 17 (88%) involving the pons. Contrast enhancement was apparent in 7 of 12 cases (58%). CONCLUSION: In the brainstem, MRI demonstrated partial or total contiguity between lesions and cisternal or ventricular CSF space, and coronal or sagittal images showed that lesions were long and tubuler.
Brain Stem* ; Magnetic Resonance Imaging* ; Medulla Oblongata ; Mesencephalon ; Multiple Sclerosis* ; Pons ; Protons ; Retrospective Studies

Medullar respiratory centers are composed of ventral and dorsal groups. A direct infarction to their structure could lead to a complete loss of respiratory drive, despite unilateral brainstem lesion is rarely associated with central respiratory dysfunction. A 70-year-old man was admitted with sudden dizziness and disequilibrium without motor weakness. Brain MRI (diffuse weight image) shows high signals intensities on left PICA territory of cerebellum and medulla oblongata including reticular formation, nucleus of tractus solitarius, nucleus ambiguus, and nucleus retroambiguus but sparing corticospinal and corticobulbar pathway. On 3rd hospital day, he had a complete loss of respiratory drive involving both autonomic and voluntary components. He didn't get the respiratory drive during CO2 retention while his consciousness and motor power were preserved.
Aged ; Brain ; Brain Stem ; Cerebellum ; Consciousness ; Dizziness ; Humans ; Infarction* ; Magnetic Resonance Imaging ; Medulla Oblongata ; Pica* ; Respiratory Center ; Respiratory Insufficiency* ; Reticular Formation

Methyl bromide is presently used as a fumigant for insects in soil, grains or fruit in storage or transport. It is a neurotoxic agent and has been responsible a number of deaths or acute poisonings among occupationally exposed persons. We report 2 patients, who had worked fumigation warehouse, presented with seizures and altered mental state. The serum concentrations of bromide were elevated 32.9 and 42.5 mg/l, respectively. Brain MRI showed bilateral symmetric high signal intensities in the splenium of corpus callosum, the globus pallidus, the quadrigeminal plate, the periaqueductal gray matter, the red nucleus, the substantia nigra, the medial lemniscus, the pontine tegmentum, the dentate nucleus, and the medulla. There was no brain lesion in the other patient. Appropriate and supervised handling of the chemical and regular education to workers are important to avoid the risk of methyl bromide poisoning.
Brain ; Edible Grain ; Cerebellar Nuclei ; Corpus Callosum ; Education ; Fruit ; Fumigation ; Globus Pallidus ; Humans ; Insects ; Magnetic Resonance Imaging ; Occupations ; Periaqueductal Gray ; Poisoning ; Red Nucleus ; Seizures* ; Soil ; Substantia Nigra ; Tectum Mesencephali

In the present study, we performed immunohistochemical studies to investigate the detailed distribution of insulin-like growth factor binding protein 7 (IGFBP7) in the central nervous system of adult rats. Twelve adult (4~6 month old) Sprague-Dawley rats were examined in this study. Immunohistochemistry using specific antibodies against IGFBP7 was performed in accordance with the free-floating method. In the present study, IGFBP7 immunoreactivity was observed in the cerebral cortex, hippocampus, brainstem, cerebellum and spinal cord. In the cerebral cortex, heavily stained neurons were seen in layers II-VI. In the hippocampus, pyramidal cells in CA1-3 region were strongly immunoreactive for IGFBP7. Strong immunoreactive neurons were also found in the supraoptic nucleus, paraventricular nucleus, periaqueductal gray and oculomotor nucleus. In the cerebellum, IGFBP7 immunoreactivity was prominent in the Purkinje cells and cerebellar output neurons. IGFBP7-immunoreactive neurons were prominent in the superior vestibular nucleus, cochlear nucleus, trigeminal motor nucleus, nucleus of the trapezoid, and facial nucleus. IGFBP7-immunoreactive neurons were also observed mainly in the anterior horn of the spinal cord. The first demonstration of IGFBP7 localization in the whole brain may provide useful data for the future investigations on the structural and functional properties of IGFBP7.
Adult ; Animals ; Antibodies ; Brain ; Brain Stem ; Carrier Proteins ; Central Nervous System ; Cerebellum ; Cerebral Cortex ; Cochlear Nucleus ; Hippocampus ; Horns ; Humans ; Immunohistochemistry ; Neurons ; Paraventricular Hypothalamic Nucleus ; Periaqueductal Gray ; Purkinje Cells ; Pyramidal Cells ; Rats ; Rats, Sprague-Dawley ; Spinal Cord ; Supraoptic Nucleus ; Trigeminal Nuclei

The aim of the present study is to examine the brainstem sites where the electrical stimulation produces a suppression of dorsal horn neuron responses of neuropathic rats. An experimental neuropathy was induced by a unilateral ligation of L5-L6 spinal nerves of rats. Ten to 15 days after surgery, the spinal cord was exposed and single-unit recording was made on wide dynamic range (WDR) neurons in the dorsal horn. Neuronal responses to mechanical stimuli applied to somatic receptive fields were examined to see if they were modulated by electrical stimulation of various brainstem sites. Electrical stimulation of periaqueductal gray (PAG), n. raphe magnus (RMg) or n. reticularis gigantocellularis (Gi) significantly suppressed responses of WDR neurons to both noxious and non-noxious stimuli. Electrical stimulation of other brainstem areas, such as locus coeruleus. (LC) and n. reticularis paragigantocellularis lateralis (LPGi), produced little or no suppression. Microinjection of morphine into PAG, RMg, or Gi also produced a suppression as similar pattern to the case of electrical stimulation, whereas morphine injection into LC or LPGi exerted no effects. The results suggest that PAG, NRM and Gi are the principle brainstem nuclei involved in the descending inhibitory systems responsible for the control of neuropathic pain. These systems are likely activated by endogenous opioids and exert their inhibitory effect by acting on WDR neurons in the spinal cord.
Analgesics, Opioid ; Animals ; Brain Stem* ; Electric Stimulation* ; Horns ; Ligation ; Locus Coeruleus ; Microinjections ; Models, Animal* ; Morphine ; Neuralgia* ; Neurons ; Periaqueductal Gray ; Posterior Horn Cells* ; Rats* ; Spinal Cord ; Spinal Nerves

Because of its broad range of activities, BDNF is being tested or considered for treatment of a variety of neurodegen-erative diseases. However, a discrepancy exists in the literature concerning the localization of BDNF-immunoreactive (IR) structures in the brain. We performed, therefore, immunohistochemistry to investigate the regional distribution of BDNF-IR neurons and axon terminals in the rat brain. The results obtained were as follows; Telencephalon : BDNF-IR neurons were found in the anterior olfactory nucleus (n.), the piriform cortex, the neocortex, the lateral septum, the claustrum, the pyramidal layer of CA2 and CA3, the basolateral amygdaloid n. and the bed n. of the stria terminalis. BDNF-IR axon terminals were localized in the lateral septum, the stratum lucidum of CA2 and CA3, the hilum, the dentate gyrus, the central amygdaloid n. and the bed n. of the stria terminalis. Diencephalon : BDNF-IR neurons were demonstrated in the medial geniculate n., the mammillary n. and the ventromedial hypothalamic n. In the anteromedial thalamic n., the anteroventral thalamic n., the paraventricular thalamic n., the lateral geniculate n. and the medial habenular n., densely stained IR terminals were found. Midbrain : BDNF-IR terminals were localized in the substantia nigra, the ventral tegmental area and the periaqueductal gray. Pons : Densely stained IR terminals were found in the ventral tegmental n. and the parabranchial n.. BDNF-IR neurons were localized in the inferior colliculus, the pontine n. and the motor trigeminal n. Medulla oblongata : BDNF-IR neurons were found in the inferior olive n. and the area postrema. IR terminals were localized in the inferior olive n., the lateral reticular n., the dorsal cap of Kooy, the n. tractus solitarious and the spinal trigeminal n. The results show that BDNF-IR neurons and terminals are distributed in numerous structures of the brain and that BDNF may be related with a various function of the regions.
Animals ; Area Postrema ; Axons* ; Basal Ganglia ; Brain* ; Brain-Derived Neurotrophic Factor ; Central Nervous System ; Dentate Gyrus ; Diencephalon ; Immunohistochemistry ; Inferior Colliculi ; Medulla Oblongata ; Mesencephalon ; Neocortex ; Neurons* ; Olea ; Periaqueductal Gray ; Pons ; Presynaptic Terminals* ; Rats* ; Substantia Nigra ; Telencephalon ; Ventral Tegmental Area