Anterior Horn Region Research Articles

IRAK-M Plays A Role in the Pathology of Amyotrophic Lateral Sclerosis Through Suppressing the Activation of Microglia.

Microglial activation plays a crucial role in the disease progression in amyotrophic lateral sclerosis (ALS). Interleukin receptor-associated kinases-M (IRAK-M) is an important negative regulatory factor in the Toll-like receptor 4 (TLR4) pathway during microglia activation, and its mechanism in this process is still unclear. In the present study, we aimed to investigate the dynamic changes of IRAK-M and its protective effects for motor neurons in SOD1-G93A mouse model of ALS. qPCR (Real-time Quantitative PCR Detecting System) were used to examine the mRNA levels of IRAK-M in the spinal cord in both SOD1-G93A mice and their age-matched wild type (WT) littermates at 60, 100 and 140days of age. We established an adeno-associated virus 9 (AAV9)-based platform by which IRAK-M was targeted mostly to microglial cells to investigate whether this approach could provide a protection in the SOD1-G93A mouse. Compared with age-matched WT mice, IRAK-M mRNA level was elevated at 100 and 140days in the anterior horn region of spinal cords in the SOD1-G93A mouse. AAV9-IRAK-M treated SOD1-G93A mice showed reduction of IL-1β mRNA levels and significant improvements in the numbers of spinal motor neurons in spinal cord. Mice also showed previously reduction of muscle atrophy. Our data revealed the dynamic changes of IRAK-M during ALS pathological progression and demonstrated that an AAV9-IRAK-M delivery was an effective and translatable therapeutic approach for ALS. These findings may help identify potential molecular targets for ALS therapy.

Effect of electroacupuncture of "Zhiyang" (GV9) and "Jizhong" (GV6) on expression of CGRP and NLRP3 in rats with spinal cord injury

To observe the effect of electroacupuncture (EA) at "Zhiyang" (GV9) and "Jizhong" (GV6) of the Governor Vessel on the expression of calcitonin gene related peptide (CGRP)and NOD-like receptor pyrin containing 3 (NLRP3) in the injured anterior horn (AH) of rats with spinal cord injury (SCI), so as to explore its mechanisms underlying improvement of SCI. Thirty-six male SD rats were randomly divided into sham operation (sham) group, model group and EA group which were further randomly allocated to 7 day (d) and 14 d subgroups (n=6 per subgroup). The SCI model was established by clamping the exposed spinal cord with an aneurysm clip. Rats of the EA group received EA of GV6 and GV9 for 30 min, once daily for 7 and 14 days, respectively. The Basso, Beattie and Bresnahan (BBB) was used to assess changes of the locomotor function on the 1st, 3rd, 7th and 14th day after SCI. The protein expression levels of CGRP, NLRP3, apoptosis-associated speck-like protein (ASC) and cysteinyl aspartate specific protease-1 (caspase-1) in the anterior horn region of the spinal cord on the 7th and 14th after SCI were detected by Western blot. The BBB scores on the 1st, 3rd, 7th and 14th d after SCI were significantly lower in the model group than in the sham group (P<0.05), whereas the expression levels of NLRP3, ASC and caspase-1 proteins on day 7 and 14 were markedly higher in the model group than in the sham group (P<0.05, P<0.01). Compared with the model group, the BBB score and CGRP expression on the 7th and 14th d were significantly increased in the EA group (P<0.05,P<0.01), while the expression levels of NLRP3, ASC and caspase-1 were obviously decreased in the EA group (P<0.01). EA of GV6 and GV9 can improve the locomotion of SCI rats, which may be associated with its function in up-regulating the expression of CGRP and down-regulating the expression of NLRP3, ASC and caspase-1 proteins in the spinal anterior horn tissue.

Applying surface-based morphometry to study ventricular abnormalities of cognitively unimpaired subjects prior to clinically significant memory decline

Ventricular volume (VV) is a widely used structural magnetic resonance imaging (MRI) biomarker in Alzheimer’s disease (AD) research. Abnormal enlargements of VV can be detected before clinically significant memory decline. However, VV does not pinpoint the details of subregional ventricular expansions. Here we introduce a ventricular morphometry analysis system (VMAS) that generates a whole connected 3D ventricular shape model and encodes a great deal of ventricular surface deformation information that is inaccessible by VV. VMAS contains an automated segmentation approach and surface-based multivariate morphometry statistics. We applied VMAS to two independent datasets of cognitively unimpaired (CU) groups. To our knowledge, it is the first work to detect ventricular abnormalities that distinguish normal aging subjects from those who imminently progress to clinically significant memory decline. Significant bilateral ventricular morphometric differences were first shown in 38 members of the Arizona APOE cohort, which included 18 CU participants subsequently progressing to the clinically significant memory decline within 2 years after baseline visits (progressors), and 20 matched CU participants with at least 4 years of post-baseline cognitive stability (non-progressors). VMAS also detected significant differences in bilateral ventricular morphometry in 44 Alzheimer’s Disease Neuroimaging Initiative (ADNI) subjects (18 CU progressors vs. 26 CU non-progressors) with the same inclusion criterion. Experimental results demonstrated that the ventricular anterior horn regions were affected bilaterally in CU progressors, and more so on the left. VMAS may track disease progression at subregional levels and measure the effects of pharmacological intervention at a preclinical stage.

Influence of electroacupuncture of "Dazhui" (EX-B2) and "Mingmen" (GV4) on NR2B expression in anterior horns of spinal cord in rats with acute spinal cord injury

To observe the influence of eletroacupuncture (EA) at "Dazhui" (EX-B2) and "Mingmen" (GV4) on expression of NR2B subunit of N-methyl-D-aspartate receptor (NMDA) in the injured anterior horn (AH) area of rats with acute spinal cord injury (SCI), so as to explore its mechanisms underlying improvement of neural repair. A total of 96 male Sprague-Dawley (SD) rats were randomly and equally divided into four groups: sham operation (sham), model, medication (Methyl-prednisone, MP) and EA (n＝24 in each group). The acute SCI model was established by using a MASCIS spinal cord impactor. EA (2 Hz, 0.5 mA) was applied to EX-B2 and GV4 for 30 min, once at 0.5 h, 12 and 24 h after SCI. Rats of the medication group were treated by tail intravenous injection of MP 30 mg/kg within 15 min (impact therapy) and 5.4 mg•kg－1•h－1 (maintaining treatment) 45 min thereafter for 23 h. The Basso, Beattie and Bresnahan (BBB) rating scale (0 to 21 points) was used to assess changes of locomotor function 6, 24 and 48 h after SCI. Histopathological changes of the injured spinal cord AH region were observed after sectioning and hematoxylin-eosin (H.E.) staining, and the expression levels of NR2B mRNA and protein of AH were measured by quantitative real-time PCR, Western blot and immunofluorescence, respectively. After SCI, the BBB scores at 6, 24 and 48 h were significantly decreased in the model group compared with those of the sham group (P<0.001), but had no remarkable changes in both medication and EA groups after the intervention in comparison with those of the model group (P>0.05). After modeling, the histopathological changes (blurred border of the grey-white matter, cellular karyopyknosis, deepening of the cytoplasmic red stain, and rupture, dissolution and disordered arrangement of myelinated nerve fibers) in the injury area of the spinal cord in the model group were apparent, the number of NR2B positive neurons and the relative expression levels of NR2B mRNA and protein were significantly increased in the model group relevant to the sham group (P<0.05). In contrast to the model group, the injured severity of the spinal cord AH region was relatively milder, and the expression levels of NR2B mRNA and protein were considerably down-regulated in both EA and MP groups (P<0.05). However, there were no significant differences between the EA and MP groups in the expression levels of NR2B mRNA and protein (P>0.05). EA at EX-B2 and GV4 may inhibit the expression of NR2B mRNA and protein in acute SCI rats, which may contribute to its action in promoting nerve repair of the injured ventricolumna area of the thoracic spinal cord.

Dynamic changes of CX3CL1/CX3CR1 axis during microglial activation and motor neuron loss in the spinal cord of ALS mouse model

BackgroundNeuron-microglia communication plays a crucial role in the motor neurons (MNs) death in amyotrophic lateral sclerosis (ALS). Neurons can express chemokine (C-X3-C motif) ligand 1 (CX3CL1), which mediates microglial activation via interacting with its sole receptor CX3CR1 in microglia. In the present study, we aimed to investigate the dynamic changes of CX3CL1/CX3CR1 axis during microglial activation and MNs loss in SOD1G93A mouse model of ALS.MethodsqPCR, western blot and immunofluorescent staining were used to examine the mRNA and protein levels and localization of CX3CL1/CX3CR1 in the anterior horn region of spinal cord in both SOD1G93A mice and their age-matched wild type (WT) littermates at 40, 60, 90 and 120 days of age. The M1/M2 microglial activation in the spinal cord tissues of SOD1G93A mice and WT mice were evaluated by immunofluorescent staining of M1/M2 markers and further confirmed by qPCR analysis of M1/M2-related cytokines.ResultsThe immunofluorescent staining revealed that CX3CL1 was predominately expressed in MNs, while CX3CR1 was highly expressed in microglia in the anterior horn region of spinal cord. Compared with age-matched WT mice, CX3CL1 mRNA level was elevated at 40 days but decreased at 90 and 120 days in the anterior horn region of spinal cords in ALS mice. Consistently, CX3CR1 mRNA level was increased at 90 and 120 days. Western blot assay further confirmed the dynamic changes of CX3CL1/CX3CR1 axis in ALS mice. Additionally, the levels of M1/M2 markers of microglia and their related cytokines in the anterior horn region of spinal cord in ALS mice were increased at 90 and 120 days. Moreover, while M1-related cytokines in ALS mice were persistently increased at 120 days, the upregulated M2-related cytokines started to decline at 120 days, suggesting an altered microglial activation.ConclusionsOur data revealed the dynamic changes of CX3CL1/CX3CR1 axis and an imbalanced M1/M2 microglial activation during ALS pathological progression. These findings may help identify potential molecular targets for ALS therapy.

Anatomic all-epiphysial tibial tunnels for anterior cruciate ligament reconstruction in skeletally immature knees may be placed without damaging the anterior meniscus root

ObjectivesThe purpose of this study was to evaluate the spatial relationship of the anterior horns of the menisci and the tibial tunnel during all-epiphysial drilling of skeletally immature specimens and identify any iatrogenic damage or destabilisation to the meniscus and meniscal root.MethodsFour skeletally immature cadaveric knee specimens (aged 9–11 years) were used to create three-dimensional models from CT images. All-epiphysial anterior cruciate ligament (ACL) tibial tunnel drilling was performed in 14 specimens (aged 7–11 years), entering the joint surface at the ACL footprint and avoided the proximal tibial physis. The anterior meniscal roots and horns were closely inspected visually and probed for stability, prior to drilling. After drilling, the meniscus and attachment points were re-evaluated for damage to the meniscus, meniscus root and probed to evaluate for destabilisation.ResultsAll-epiphysial tunnels entered the joint at the anatomic ACL tibial footprint. Direct visual inspection of the menisci demonstrated an absence of damage to either meniscus or anterior horn regions in all specimens. Probing and traction of the medial and lateral meniscal tissue did not demonstrate evidence of instability or destabilisation of the anterior horn or meniscus root before or after drilling. All tunnels were circumferentially intact at the joint surface, with no evidence of superior tunnel perforation due to shallow tunnel angle.ConclusionIn this study, tunnel placement did not produce damage to either meniscus, nor noticeably destabilise the meniscal roots. This study also demonstrated that drill holes can be placed within the ACL footprint without entering the joint on the proximal tibia surface anterior to the ACL attachment, although the ‘safe zone’ for drill hole placement is limited. All-epiphysial ACL tibial tunnels can create a large aperture at the tibial joint surface, but these tunnels can be placed at the anatomic footprint of the ACL, without causing gross anterior medial or lateral meniscus horn or root injury.

Identification of 17 Highly Expressed Genes within Mouse Lumbar Spinal Cord Anterior Horn Region from an In-Situ Hybridization Atlas of 3430 Genes: Implications for Motor Neuron Disease.

In an effort to find possible new gene candidates involved in the causation of amyotrophic lateral sclerosis (ALS), a prior version of the on-line brain gene expression atlas GENSAT was extensively searched for selectively intense expression within spinal motor neurons. Using autoradiographic data of in-situ hybridization from 3430 genes, a search for selectively intense activity was made for the anterior horn region of murine lumbar spinal cord sectioned in the axial plane. Of 3430 genes, a group of 17 genes was found to be highly expressed within the anterior horn suggesting localization to its primary cellular constituent, the alpha spinal motor neuron. For some genes, an inter-relationship to ALS was already known, such as for heavy, medium, and light neurofilaments, and peripherin. Other genes identified include: Gamma Synuclein, GDNF, SEMA3A, Extended Synaptotagmin-like protein 1, LYNX1, HSPA12a, Cadherin 22, PRKACA, TPPP3 as well as Choline Acetyltransferase, Janus Kinase 1, and the Motor Neuron and Pancreas Homeobox 1. Based on this study, Fibroblast Growth Factor 1 was found to have a particularly selective and intense localization pattern to the ventral horn and may be a good target for development of motor neuron disease therapies; further research is needed.

Clinical and neuroimaging features of enterovirus71 related acute flaccid paralysis in patients with hand-foot-mouth disease

ObjectiveTo investigate clinical and neuroimaging features of enterovirus71 (EV71) related acute flaccid paralysis in patients with hand-foot-mouth disease. MethodsNine patients with acute flaccid paralysis met the criterion of EV71 induced hand-foot-mouth disease underwent spinal and brain MR imaging from May 2008 to Sep 2012. ResultsOne extremity flaccid was found in four cases (3 with lower limb, 1 with upper limb), two limbs flaccid in three cases (2 with lower limbs, 1 with upper limbs), and four limbs flaccid in two cases. Spinal MRI studies showed lesion with high signal in T2-weighted images (T2WI) and low signal T1-weighted images (T1WI) in the spinal cord of all nine cases, and the lesions were mainly in bilateral and unilateral anterior horn of cervical spinal cord and spinal cord below thoracic 9 (T9) level. In addition, the midbrain, pons, and medulla, which were involved in 3 cases with brainstem encephalitis, demonstrated abnormal signal. Moreover, spinal cord contrast MRI studies showed mild enhancement in corresponding anterior horn of the involved side, and strong enhancement in its ventral root. ConclusionsEV71 related acute flaccid paralysis in patients with hand-foot-mouth disease mainly affected the anterior horn regions and ventral root of cervical spinal cord and spinal cord below T9 level. MR imaging could efficiently show the characteristic pattern and extent of the lesions which correlated well with the clinical features.

Neurologic complications in children with enterovirus 71-infected hand-foot-mouth disease : clinical features, MRI findings and follow-up study

To explore the clinical and magnetic resonance imaging (MRI) characteristics and the follow-up outcomes of neurologic complications in children with enterovirus 71-infected hand-foot-mouth disease. The clinical and MRI manifestations and follow-up outcomes in 35 children, at Second Affiliated Hospital, Wenzhou Medical College from August 2008 to November 2010, hospitalized with neurologic complications of enterovirus 71-infected hand-foot-mouth disease were retrospectively analyzed. Six children with aseptic meningitis presented the clinical symptoms and signs of meningitis. Five of them showed subdural effusion and ventriculomegaly, or both on MRI. At follow-ups, neurologic sequel could not be found. Among 24 cases with brainstem encephalitis, there were myoclonic jerks and tremor, ataxia, or both (grade I disease, n = 12), myoclonus and cranial-nerve involvement (grade II disease, n = 4), and cardiopulmonary failure after brain-stem infection (grade III disease, n = 8). In patients with brainstem encephalitis, lesions were predominantly located at the posterior portions of medulla and pons with hypointensity on T1WI and hyperintensity on T2WI. Cerebellar dentate nucleus, caudate nucleus and lenticular nucleus could also be involved. At follow-ups, the patients with mild symptoms had no neurologic sequel and the lesions within brain stem became small or vanished in most cases. While in the majority of serious patients, neurologic sequel could be found and the lesions located at brain stem became encephalomalacia. Fourteen cases with acute flaccid paralysis presented acute limb myasthenia with tendon reflex and muscular tension decreased. On spinal MRI, the lesions predominantly involved anterior horn regions of spinal cord with hypointensity on T1WI and hyperintensity on T2WI. Most patients improved their muscle strength and most lesions of spinal cord became smaller or vanished during follow-ups. MRI is the most effective modality of diagnosis and follow-up for neurologic complications in children with enterovirus 71-infected hand-foot-mouth disease. On MRI, the lesions mainly involve the anterior horn of spinal cord, medulla oblongata and pons. At follow-ups, most patients have no neurologic sequel and the visualized lesions will be absorbed after active treatment.

A Case of Monomelic Amyotrophy of the Upper Limb

Monomelic amyotrophy of the upper limb or Hirayama disease is mostly considered as an anterior horn disorder resulting from local ischemia, triggered by arterial compression from an anterior shifting of the posterior cervical dura upon neck flexion. However, such a dural shifting is not universally seen. We report on a Caucasian male patient who developed a slowly progressive unilateral distal hand weakness in his teens. His clinical and electromyographic findings were consistent with Hirayama disease. Local anterior cervical cord atrophy was observed without dural shifting on the dynamic magnetic resonance imaging. Axial magnetic resonance imaging demonstrated signal changes of "snake-eye" appearance in the cervical anterior horn region, similar to ischemic myelopathies caused by various etiologies. This case illustrated that even without dural shifting, a mechanism of anterior spinal cord ischemia could still be responsible for the pathogenesis of Hirayama disease.

Spatiotemporal alteration of phospholipids and prostaglandins in a rat model of spinal cord injury

We determined quantitative and qualitative alterations in lipids during the occurrence and progression of spinal cord injury (SCI) in rats to identify potential clinical indicators of SCI pathology. Imaging mass spectrometry (IMS) was used to visualize twelve molecular species of phosphatidylcholine (PC) on thin slices of spinal cord with SCI. In addition, twelve species of phospholipids and five species of prostaglandins (PGs) were quantified by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) of lipid extracts from control/injured spinal cords. Unique distribution patterns were observed for phospholipids with different fatty acid compositions, and distinct dynamic changes were seen in both their amounts and their distributions in tissue as tissue damage resulting from SCI progressed. In particular, PCs containing docosahexaenoic acid localized to the large nucleus in the anterior horn region at one day post-SCI and rapidly decreased thereafter. In contrast, PCs containing arachidonic acid (AA-PCs) were normally found in the posterior horn region and were intensely and temporarily elevated one week after SCI. Lysophosphatidylcholines (LPCs) also increased at the same SCI stage and in regions with elevated AA-PCs, indicating the release of AA and the production of PGs. Moreover, LC-ESI-MS/MS analysis of lipid extracts from the spinal cord tissue at the impact site demonstrated a peak in PGE2 that reflected the elevation/reduction pattern of AA-PCs and LPC. Although further investigation is required, we suggest that invasive immune cells that penetrated from the impaired blood-brain barrier at 1-2 weeks post-SCI may have produced LPCs, released AA from AA-PCs, and produced PGs in SCI tissue at sites enriched in AA-PCs/LPC.

Motor Neuron Disease Associated with Voltage-Gated Potassium Channel Antibodies

Introduction: Antibodies to voltage-gated potassium channels have been implicated in causing a host of peripheral and central nervous system disorders. However, the presence of these antibodies has not been previously associated with motor neuropathy. We describe the first case of acquired motor neuron disease associated with voltage-gated potas-sium channel antibodies. Case Report: The patient is an 81-year-old female who developed signs and symptoms of an idiopathic motor neuron disease. The patient was found to have increased antibodies to voltage-gated potassium chan-nels in the absence of a known metastatic or autoimmune process. Magnetic resonance imaging of the cervical spine demonstrated increased signal in the anterior horn regions of the cervical and upper thoracic spinal cord on T2-weighted imaging. The patient’s disease progression was refractory to both intravenous immunoglobulin and ster-oid therapy. Conclusion: Voltage-gated potassium channels may be causal or simply associated with motor neuron disease; this relationship needs to be elucidated. Testing for these antibodies may be warranted in cases of idiopathic rapidly progressing motor neuron disease.

Clinical study of 15 children with hand foot and month disease and acute flaccid paralysis

Objective To discuss the clinical characteristics and prognosis of 15 children with hand foot and mouth disease (HFMD) and acute flaccid paralysis (AFP) who were admitted to Beijing Ditan Hospital during the outbreak of HFMD in 2008. Method The epidemiology, clinical manifestations, cerebrospinal fluid (CSF),magnetic resonance imaging and prognosis of 15 children with HFMD and AFP were retrospectively reviewed. The recovery of the patients' affected extremities were monitored for 4 weeks. Results The mean age of these patients was (22.47 ± 20.68) months (range: 5～72 months). Acute paralysis developed (3.47 ± 1.68) days after the onset of fever and progressed to maximum severity within (1～2) days. Poliomyelitis-like syndrome was observed in all cases. Of the 15 cases, 10 had monoplegia of lower limbs, two had paraplegia, one had monoplegia of upper limbs and two had quadriplegia. In these cases, the muscle power varied from level 0 to level 4, and six even showed no muscle power in their affected extremities. Thirteen cases developed neurologic complications (encephalitis, meningitis or ataxia) and three had transient urinary retention. Cerebrospinal MRI examination in eight cases showed hyperintense lesions on T2-weighted images, predominantly in the impaired anterior horn regions of the spinal cord (C2～C7 for cases with upper extremity impairments and T12～L1 for cases with lower extremity impairments), and displayed long T1 signals and long T2 signals. In addition, the midbrain, brain-stem or medulla was also involved in four cases who also contracted encephalitis or meningitis. The muscle strength in 11 patients with single lower extremity impairment showed improvements in the distal limb muscles within 4～8 days, and the other cases showed recovery 2～3 weeks later. Conclusions HFMD in combination with AFP most commonly occurs in children aged less than 2 years old. Acute paralysis develops during the early stage of infection and progresses to a maximum severity within 2 days. In most cases described here, paralysis occurred in a single lower extremity and recovered more rapidly than those with all four limbs affected or with single upper extremity impairment . MRI examination is particularly valuable for the diagnosis and prognosis of AFP because of its high sensitivity and accuracy. Key words: Acute flaccid paralysis (AFP); Hand; foot and mouth disease (HFMD); Encephalomyelitis; Non-polio enterovirus(NPEV)

膝に対するＭＲＩの検討 鏡視所見との比較

161 patients, 169 knees were evaluated with magnetic resonance imaging (MRI) and arthroscopy. MR findings and arthroscopic findings agreed in 74.6% of medial menisci, 74.6% of lateral menisci, 92.3% of anterior cruciate ligaments (ACL), 95.3% of posterior cruciate ligaments (PCL). The results between JOA (the Japanese Orthopaedic Association) -authorized orthopedists and junior residents were almost similar. On the basis of arthroscopic findings, false-positive and false-nagative cases of MRI were studied. Intrameniscal signal communicating with a meniscal articular surface was an important MRI finding for meniscal tear at arthroscopy. False-positive findings at MRI of the anterior and posterior horn regions of menisci may reflect the inability to completely and accurately visualize the meniscus with arthroscopy. False-negative findings at MRI of menisci often occurred in small tears. It may be difficult to accurately evaluate the region around the popliteus tendon with MRI. False-positive findings at MRI of the ACL may result from the partial volume effect because of proliferating synovium. False-positive findings of the PCL occurred, because ACL deficiency brings the sigmoid deformity at MRI of the PCL. False-negative findings of cruciate ligaments resulted from small tears.

A monoclonal antibody distinguishes anterior horn cells of human embryonic spinal cord during a transient period of development

Monoclonal antibodies were prepared by using the anterior horn region of human embryonic spinal cord as immunogen. To increase the specificity of the immune response towards the anterior horn cells, mice were first injected with antigens from the posterior horn and then immunosuppressed with cyclophosphamide; subsequently antigens from the anterior horn were injected. One of the monoclonal antibodies recognizes a small population of anterior horn cells of human embryonic spinal cord during a transient period of development (9–10th embryonic week); these cells are probably motoneurons according to their location in the spinal cord, their positive staining for acetylcholinesterase and their large nuclei. The staining pattern has a special axial distribution as it is limited to the cervical and thoracic regions of the spinal cord. The antibody is species-specific and shows a high degree of tissue specificity. Since this antibody distinguishes a small group of anterior horn cells in the spinal cord during a specific developmental stage, it opens stimulating perspective for further investigation on the nature of the antigen and its putative role during the development of the human embryonic spinal cord.

Ubiquitin gene expression in brain and spinal cord in motor neurone disease

A restriction fragment of the coding region of a human ubiquitin gene has been used in Northern analyses of RNA prepared from human motor cortex and anterior horn region of cervical spinal cord. The analyses show that there is a substantial increase (approximately two-fold) in the expression of a polyubiquitin gene in motor cortex and spinal cord from patients with motor neurone disease compared to these tissues from control cases. Polyubiquitin gene expression in other organisms is associated with physical or chemical cell stresses. The data indicate that the primary stresses which result in the generation of ubiquitinated filamentous inclusion bodies in neurones in motor neurone disease also result in increased transcription of a gene coding for a polyprotein of ubiquitin.

Therapeutic trial of intrathecal thyrotropin-releasing hormone (TRH) and a TRH-analogue in amyotrophic lateral sclerosis (ALS).

Thyrotropin-releasing hormone (TRH) is widely distributed in the central nervous system (CNS) and possibly plays an important role as a facilitatory neuromodulator and/or ergotrophic factor independent of its endocrine action[6,7,9,18]. It has been found in high concentrations in the anterior horns of the spinal cord and in cranial nerve nuclei of the brainstem, it shows excitatory actions on lower motor neurons in laboratory animals, and it has trophic effects on ventral spinal cord cultures[15]. In cats, TRH improved neurologic recovery from experimental spinal injury [5]. Its concentrations in the anterior horn regions of ALS patients on the other hand are decreased, its levels in the cerebrospinal fluid (CSF) seem to be reduced[3,12]. Engel et al.[2] reported for the first time a transient improvement of muscle strength and spasticity in ALS under very high intravenous doses of TRH (2 - 19 mg/min). Further trials with subcutaneous applications were promising and showed some clinical benefit up to 12 days[4]. Other intravenous studies had negative results[13]. Imoto et al.[8] injected TRH intramuscularly (4 mg daily) without unequivocal effects. TRH has a plasma half-life of only 4-5 min because of rapid enzymatic degradation, and its ability to cross the blood brain barrier is only limited. These difficulties might be circumvented by intrathecal application or by the use of TRH-analogues which have a protracted biological stability, therefore enhanced bioavailability to the CNS and enhanced neuro-pharmacological potency[10,11].

Serotonin-containing nerve fibers in the rat spinal cord: electron microscopic immunohistochemistry.

The ultrastructure of the serotonin (5HT) system in the spinal cord of rats was studied by an immunohistochemical peroxidase-antiperoxidase (PAP) method. Under the light microscope, 5HT immunoreactive staining was observed as brown-colored dots in the anterior horn, lateral horn, posterior horn and pericentral canal region. These positively staining dots were probably indicative of 5HT immunoreactive varicosities and nerve terminals. At the ultrastructural level, 5HT immunoreactive nerve fibers appeared as darkly stained varicosities with PAP positive large electron dense vesicles (80-100 nm), as well as small clear vesicles (30-40 nm) finely coated with PAP immunoreactive products. In the anterior horn, some of the 5HT immunoreactive structures were clearly nerve terminals forming asymmetric synaptic contact with soma or dendrites of the anterior horn cells. In the lateral horn, posterior horn and pericentral canal region, however, only 5HT positive varicosities were detected.

Intrathecal thyrotropin-releasing hormone therapy of amyotrophic lateral sclerosis.

Six patients with amyotrophic lateral sclerosis were given from 800 to 4000 micrograms of thyrotropin-releasing hormone (TRH) intrathecally for a period of 2-6 months. The progressive course of this disease, manifested by increasing atrophy, paralysis and disability score, was not altered. This supports the hypothesis that the decrease in TRH content in the anterior horn region is secondary to the cellular destruction. TRH appears to play no significant role in the pathogenesis of amyotrophic lateral sclerosis.

Distribution and Life History of Rat Brain Tumors Induced by Human Adenovirus Type 12 in their Early Stages of the Oncogenesis

Newborn rats were intracranially inoculated with human adenovirus type 12 within 24 hours after birth and their brains were sequentially investigated by conventional histological techniques and autoradiography to clarify the early process of tumor growth. At the end of the 2nd week atypical cells having bizarre configuration first appeared singly in the tapetum. From the end of the 3rd week small clusters of slightly atypical subependymal cells ("abnormal clusters") appeared in the subependymal area. From the end of the 4th week a few "microtumors" showing compact nodular growth of atypical glial cells were observed among the "abnormal clusters". These early neoplastic changes in the rat brains had close relationship to subependymal cells. The perinatal subependymal cells showed most dense distribution in the subependymal area of lateral ventricle with open ventricular space ("open ventricular area") especially in the region of anterior horn. In contrast, the microtumors and the enlarged tumors were recognized much more in number in the subependymal area of bulbus olfactorius and tapetum where ventricular cavities closed in the young period of maturation ("closed ventricular area"). "Abnormal clusters" were located in both of the areas with more preponderence in the open ventricular area. The reasons for this discrepancy of occurrence were discussed from the viewpoint of environmental factors. Subsequent investigation revealed that the average number of microtumors, after reaching its peak at the end of the 5th week, diminished gradually and, finally, only one or two enlarged tumors were found per each tumor-bearing animal. The mechanisms for this phenomenon are open to further investigation.