Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002736 (amyotrophic lateral sclerosis)
 19,048 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To elucidate the relevance of metabotropic glutamate receptors (mGluRs) to the selective vulnerability of motor neurons in the spinal cord in patients with amyotrophic lateral sclerosis (ALS), we investigated the distribution of mRNAs coding mGluR1-5 in the normal human spinal cord. The mRNAs for mGluR1, 4 and 5 were observed in the spinal gray matter, whereas mGluR2 mRNA was absent in the spinal cord and mGluR3 mRNA was displayed only on glial cells in the white matter. Signals for mGluR1 and mGluR5 were enriched in the dorsal horn, while mGluR4 mRNA was abundant in the ventral horn. Since agonists to group I mGluRs (mGluR 1 and 5) have been demonstrated to have neuroprotective effects on spinal motor neurons, less expression of mRNAs coding mGluR1 and mGluR5 in the ventral horn than in the dorsal horn may be implicated in the selective susceptibility of spinal motor neurons in ALS.
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PMID:Expression of metabotropic glutamate receptor mRNAs in the human spinal cord: implications for selective vulnerability of spinal motor neurons in amyotrophic lateral sclerosis. 1153 35

Excitotoxicity, which is mediated by the excessive activation of glutamate receptors, has been implicated in the pathogenesis of amyotrophic lateral sclerosis (ALS). There is substantial information about the distribution and function of ionotropic glutamate receptors in the spinal cord, although the role of metabotropic glutamate receptors (mGluRs) is poorly understood in this region of the brain, particularly under pathological conditions. We used immunocytochemistry to study the general distribution of group I and group II mGluR immunoreactivity in the human spinal cord, as well as the cell-specific expression of these receptors. We also investigated whether mGluR expression was altered in the spinal cord of patients with sporadic and familial ALS. Immunocytochemical analysis of control human spinal cord demonstrated that mGluR1alpha and mGluR5 (group I mGluRs) were highly represented in neuronal cells throughout the spinal cord. mGluR1alpha showed the highest relative level of expression in ventral horn neurons (laminae VIII and IX), whereas intense mGluR5 immunoreactivity was observed within the dorsal horn (superficial laminae I and II). Group II mGluRs (mGluR2/3) immunoreactivity was mainly concentrated in the inner part of the lamina II. With respect to specific neuronal populations, mGluR2/3 and mGluR5 appeared to be most frequently expressed in calbindin-containing and calretinin-containing cells, respectively. In control spinal cord only sparse astrocytes showed a weak to moderate mGluR immunoreactivity. Regional differences in immunoreactivity were apparent in ALS compared to control. In particular, mGluR expression was increased in reactive glial cells in both gray (ventral horn) and white matter of ALS spinal cord. Upregulation of mGluRs in reactive astrocytes may represent a critical mechanism for modulation of glial function and changes in glial-neuronal communication in the course of neurodegenerative diseases.
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PMID:Immunohistochemical localization of group I and II metabotropic glutamate receptors in control and amyotrophic lateral sclerosis human spinal cord: upregulation in reactive astrocytes. 1167 16

Accumulating evidence indicates that alterations in glial activation and disturbances in glial glutamate metabolism may contribute to the pathogenesis of amyotrophic lateral sclerosis (ALS). Metabotropic glutamate receptors (mGluRs) are involved in glutamate homeostasis as well as in glial proliferation. Using in situ hybridization and immunohistochemistry we found a strong upregulation of group I and group II mGluR mRNA and protein in ALS spinal cord as compared to controls (mGluR5 > mGluR1 > mGluR2/3). In vitro, the mGluR group I agonist 3,5-dihydroxyphenylglycine induced proliferation in chick spinal cord astroglial cultures. Moreover, addition of cerebrospinal fluid (CSF) from ALS patients resulted in significantly higher proliferation rates than control CSF. In both cases, the effect could be blocked by addition of the mGluR group I antagonist 1-aminoindan-1,5-dicarboxylic acid. Taken together, our data suggest that stimulation of glial mGluRs through mediators present in the CSF may contribute to glial proliferation and astrogliosis in ALS.
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PMID:Glial proliferation and metabotropic glutamate receptor expression in amyotrophic lateral sclerosis. 1533 Mar 38

Metabotropic glutamate receptors alter the vulnerability of neurons to excitotoxic damage and are reported to display abnormal expression in the central nervous system of ALS patients. Using reverse transcriptase polymerase chain reaction, we investigated the mRNA expression of specific metabotropic glutamate receptor subtypes in T lymphocytes of 20 patients with sporadic ALS, compared with healthy age-matched control subjects and patients with other neurological disorders. The levels of metabotropic glutamate receptor 2 mRNA were markedly reduced, whereas the expression of other subtypes (1b, 3, 8) was similar to control levels. Our findings may provide a reliable peripheral marker of the glutamatergic dysfunction that characterizes ALS.
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PMID:Reduced expression of metabotropic glutamate receptor 2mRNA in T cells of ALS patients. 1624 Mar 62