No abstract available.
Biofeedback, Psychology* ; Motor Neurons*

Hirayama disease, juvenile muscular atrophy of the distal upper limb, is a rare disease predominantly affecting the anterior horn cells of the cervical spinal cord in young men. This cervical myelopathy is associated with neck flexion. It should be suspected in young male patients with a chronic history of weakness and atrophy involving the upper extremities followed by clinical stability in few years. Herein, we report 2 cases of Hirayama disease on emphasis of diagnostic approach and describe the pathognomonic findings at flexion magnetic resonance imaging.
Anterior Horn Cells ; Atrophy ; Cervical Cord ; Humans ; Magnetic Resonance Imaging ; Male ; Motor Neuron Disease* ; Motor Neurons* ; Neck ; Rare Diseases ; Spinal Cord Diseases ; Spinal Muscular Atrophies of Childhood ; Upper Extremity

Spinal muscular atrophy(SMA) is a genetic disorder of the motor neurons that cause muscular weakness and muscular atrophy due to anterior horn cell degeneration. Classic spinal muscular atrophy patient is caused by mutation in the chromosome 5(q11.2-q13.3), and the majority of the patient shows homozygous deletion of the telomeric survival motor neuron(SMN) gene in the chromosome 5. Deletion of exon 7 and 8 of the SMN gene and deletion of exon 4 and 5 of the neuronal apoptosis inhibitory protein(NAIP) are typically observed in SMA patients. The SMN protein plays a role in an essential cell metabolism process, the splicing of pre mRNA in the spliceosomes. We report a 7 month old male with SMA. He showed rapidly aggrdvatial muscular weakness and died at 7 months. His DNA analysis proved deletion of exon 7 and 8 of the telomeric copy of the SMN gene.
Anterior Horn Cells ; Apoptosis ; Chromosomes, Human, Pair 5 ; DNA ; Exons* ; Humans ; Infant ; Male ; Metabolism ; Motor Neurons* ; Muscle Weakness ; Muscular Atrophy ; Muscular Atrophy, Spinal* ; Neurons ; RNA Precursors ; Spliceosomes

STUDY DESIGN: There is a prospective study of 80 Sprague-Dawley rats which were made at the spinal cord lesion T5/6 level, sparing only one ventral quadrant. We monitered medullary reticulospinal neurons(RtN) evoked potentials at the L2/3 level which laminectomy was performed. OBJECTIVE: to investigate changes in the physiological responses of motor neurons to stimulation of the medullary reticular formation following partial spinal cord lesions sparing only the ventral quadrant. SUMMERY AND BACK GROUND DATA: There were many report that the animals with spinal cord lesion recovered well-coordi-nated fourlimb locomotion within 2-3 weeks. The time course of the functional recovery of this hindlimb locomotion was cor-related with the recovery of motor evoked potentials(MEP), which originate from reticular nuclei. Therefore, it was hypothe-sized that the return of locomotor function after incomplete spinal cord injury may partially rely on the reorganization of descending inputs to ventral horn neurons previously occupied by damaged afferents. MATERIALS AND METHODS: Total 80 Sprague-Dawley rats were used in this study. Under sterile conditions, spinal cord lesions were made at the T5/6 level using a No. 11 blade, sparing only one ventral quadrant. The animals allowed to survive from one day to 61 days. To monitor RtN evoked potentials, laminectomies were performed at L2/3 level. Field potentials were recorded using a glass microelectrode filled with 2 M NaCl(1.5-2.0 M Ohm). Cord dorsum potentials were also epidurally monitored at L2/3 using a pair of teflon-coated wires. The gigantocellular reticular nucleus ipsilateral to the spared ventral cord was stimulated using a monopolar tungsten microelectrode. RESULTS: The field potentials generated in the ventral horn of the lumbar cord were recorded bilaterally. In some animals field potentials were monitored just before and right after the spinal cord lesion. 1) Following spinal cord lesion at T5/6, the amplitude of RtN evoked potentials declined significantly in the L2/3 ventral gray matter of the completely lesioned side. Field potentials monitored below the ipsilaterally spared ventral quadrant remained unchanged. Depressed RtN evoked potentials in the ventral cord gradually increased during the next four weeks, and finally reached greater than 4 times of the amplitude monitored on the contralateral side. 2) The sites in which field potentials could be monitored in the lumbar spinal cord were mapped. In normal rats, the largest field was monitored near the ventral margin of the gray matter. On the other hand, in spinal cord injured ani-mals, the largest field potentials were located in more dorsal aspects of the ventral horn, suggesting a structural reorganization of the descending inputs has taken place. CONCLUSION: The RtN evoked potentials in the ventral horn increased gradually for several weeks after the injury. The returned RtN evoked potentials below the completely lesioned side of spinal cord were larger than those seen in normal spinal cord. The time course of returning evoked potentials below the lesioned side of the spinal cord seems to coincide with the resti-tution of same-side hindlimb locomotion.
Animals ; Anterior Horn Cells ; Evoked Potentials ; Evoked Potentials, Motor* ; Glass ; Hand ; Hindlimb ; Horns ; Laminectomy ; Locomotion ; Microelectrodes ; Motor Neurons ; Neurons* ; Prospective Studies ; Rats* ; Rats, Sprague-Dawley ; Reticular Formation ; Spinal Cord Injuries* ; Spinal Cord* ; Tungsten

The experiments were carried out on adult Sprague-Dawley rats. We investigated the discharge response of respiratory neurons (RNs) in the pre-Bözinger complex (PBC) to electrical stimulation of the facial nucleus in which the motor neurons were retrogradely degenerated and the antagonistic effects of microiontophoresis of CNQX, bicuculline (BIC), strychnine (Stry) and atropine on the discharge responses of the neurons. In 12 rats with retrograde degeneration of the facial motor neurons, 116 RNs in the PBC ipsilateral to the facial nerve sectioned were extracellularly recorded. The response of pre-inspiratory (Pre-I) (24 / 26) and inspiratory (I) (30 / 35) neurons to the electrical stimulation of the facial nucleus was mainly excitatory, and the response of expiratory (E) (20 / 22) and inspiratory-expiratory phase-spanning (I-E) (28 / 33) neurons was mainly inhibitory. CNQX partially or completely block the excitatory effect of the stimulation on Pre-I (18 / 24) and I (23 / 27) neurons. Stry could partially or completely block the immediate transient inhibition on Pre-I (12 / 18) and I (14 / 23) neurons and the inhibitory effect on I-E (20 / 28) and E (9 / 16) neurons induced by the stimulation. BIC partially or completely blocked the inhibitory effect on I-E (22 / 25) and E (9 / 9) neurons induced by the stimulation. Atropine did not have obvious influence on the response of RNs to the stimulation. These results suggest that non-motoneurons in the facial nucleus may participate in the modulation of respiration by affecting the activities of RNs in the PBC and that Glu, GABA and Gly serve as neurotransmitters or modulators to regulate the activities of the RNs in the PBC and hence the rhythmic respiratory movement.
Animals ; Electric Stimulation ; Facial Nerve ; physiology ; Female ; Glutamic Acid ; metabolism ; Glycine ; metabolism ; Male ; Medulla Oblongata ; physiology ; Motor Neurons ; physiology ; Neurons ; physiology ; Neurotransmitter Agents ; metabolism ; Rats ; Rats, Sprague-Dawley ; Respiration ; Respiratory Center ; physiology ; gamma-Aminobutyric Acid ; metabolism

Kennedy's disease is an adult onset form of motor neuron disease characterized by progressive proximal and bulbar muscle weakness. The authors report the anaesthetic management of a 43-year-old man with Kennedy's disease who underwent elective orthopaedic surgery under spinal anaesthesia. The anaesthetic implications of this X-linked lower motor neuron disorder are discussed, and guidelines for safe anaesthetic management are suggested.
Adult ; Humans ; Motor Neuron Disease ; Motor Neurons ; Muscle Weakness

Small cortical strokes can produce predominant isolated weakness in a particular group of fingers: radial or ulnar. The traditional views are of point-to-point representations of each finger to neurons located in the precentral gyrus of the motor cortex such that the neurons of the radial fingers are located laterally and those of the ulnar fingers are located medially. We present a case of isolated weakness of middle, ring, and little fingers due to a small cortical infarction in the medial precentral gyrus.
Fingers* ; Infarction* ; Motor Cortex ; Neurons ; Stroke

No abstract available.
Motor Neurons* ; Urinary Bladder, Neurogenic* ; Urodynamics*

Animals ; Mice ; Motor Neurons/physiology* ; Spinal Cord

The purpose of this study was to investigate any relationship between the geometric factors of synaptic contacts of muscle spindle afferent terminals and masseteric motor neurons in the trigeminal motor nucleus. Terminals from the masseteric muscle spindle afferents were stained with intra-axonal injection of HRP and were examined electronmi-croscopically with serial sections at the central and peripheral regions of trigeminal motor nucleus of the cat. The number of terminals examined were 76 in peripheral and 105 in central region. The results obtained were as follows. 1. Most of the labeled terminals showed simple synaptic connectivity. Each terminals in peripheral and central region made synaptic contact with 1 to 5 neuronal profiles. Two or three labeled terminals were occasionally seen to make synaptic contact with the same dendrite. 2. The average number of postsynaptic proximal dendrite per labeled terminal was higher in the central region than in the peripheral region. In contrast, that of postsynaptic distal dendrite per labeled terminal was higher in the peripheral region than in the central region. 3. The average diameter of postsynaptic dendrites in the central region was larger than that in the peripheral region. This imply terminals in the peripheral region contacted with further distal part of the distal dendrite than that in the central region. These results indicate that synaptic connectivity associated with the spindle afferents from masseteric muscle is different according to their geometric location within the trigeminal motor nucleus and suggest that there will be precise interrelationship between the morphology, pattern of synaptic connectivity and functions of muscle spindle afferents.
Animals ; Cats* ; Dendrites ; Motor Neurons ; Muscle Spindles* ; Neurons