Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004134 (ataxia)
 15,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It has been reported that thyrotropin-releasing hormone (TRH) improves the ataxia of cerebellar type. The mechanism of action is unclear. As well recognized, GABA (gamma aminobutyric acid) is an important neurotransmitter in cerebellar system. So, if TRH acts on cerebellum, it is expected that the GABA metabolism will be modified by in vivo or in vitro TRH application. The purpose of this experiment is to clarify whether or not TRH affects on GABA system in cerebellar system. The first experiment was to determine the effect of TRH on the two GABA related enzyme activities, that is, GAD (glutamic acid decarboxylase) and GABA-T (GABA-transaminase). TRH was intraperitoneally injected at a dose of 5 mg/kg. In mouse brains, the two enzyme activities of hindbrains increased after 60 minutes. Next experiment assaying GAD activities at two parts of hindbrain revealed that the increase in hindbrain observed above was due to marked increase in brain-stem (p less than 0.001), but not in cerebellum itself in which the GAD activities decreased (p less than 0.05). On the other hand, in the forebrains, the same dose of TRH failed to change both GAD and GABA-T activities. In order to ascertain the effect more precisely, we assayed GAD activities at seven parts of the brain of Wistar male rats. By this experiment, it was found that GAD activities increase at two portions, namely, at thalamo-midbrain after 30 minutes and at pons-medulla after 180 minutes of TRH injection (p less than 0.05, in both). Other five portions, including cerebellum, showed no significant change of GAD activities.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Effect of thyrotropin releasing hormone (TRH) on GABA (gamma aminobutyric acid) metabolism in mouse and rat brains: as to the activities of GAD (glutamic acid decarboxylase), GABA-T (GABA-transaminase) and GABA re-uptake]. 393 48

In an attempt to elucidate molecular pathogenesis of ataxia without cytological abberations in the cerebellum, Rolling Mouse Nagoya (C3Hf/Nem-rol) was used to study distribution of GABA receptors in membrane fractions. Among muscimol binding sites of various regions in the ataxic CNS, those in pons and medulla were significantly decreased (P less than 0.001) compared with control and non-ataxic heterozygote CNS, followed by cerebellum at a lower degree of significance (P less than 0.01). The kinetic studies demonstrated that dissociation constants of high- and low-affinity binding sites of muscimol of each control and those of ataxic mutant mouse were similar, i.e., KH = 41 nM and KL = 1.1 microM, respectively. GAD in the various regions was assayed, and it showed higher activity in the thalamus and hypothalamus, and lower activity in the cerebellum, of the ataxic mutant mouse as compared to that of the control mouse.
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PMID:Distribution and characterization of the GABA receptors in the CNS of ataxic mutant mouse. 608 75

BDNF or vehicle were administered by unilateral supranigral infusion in normal and chronically lesioned MPTP-treated common marmosets (Callithrix jacchus) for four weeks and locomotor activity, disability and response to apomorphine were assessed with nigral TH, GFAP and GAD immunoreactivity and striatal [3H]mazindol autoradiography. Selective contraversive orientation and ipsilateral neglect evolved in MPTP-treated marmosets receiving BDNF with no significant difference in disability or locomotor activity when compared to the vehicle-infused group. Apomorphine produced an ipsiversive rotational bias in BDNF-treated animals. In normal animals infused with BDNF contralateral neglect, ipsiversive turning, postural instability and ataxia rapidly evolved. In MPTP-treated marmosets BDNF caused increased ipsilateral striatal [3H]mazindol binding with increased somatic size and staining intensity in GAD-immunoreactive cells and a 10-20% loss of nigral TH-immunoreactive cells with increased GFAP staining. In normal common marmosets, both vehicle and BDNF infusion decreased nigral TH-immunoreactivity. Chronic supranigral infusion of BDNF alters motor behaviour and spatial attention in MPTP-treated marmosets which may reflect altered function in residual nigral dopaminergic neurons and brainstem GABAergic neurons and in normal animals produces behavioural and histological signs of nigrostriatal hypofunction.
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PMID:Chronic supranigral infusion of BDNF in normal and MPTP-treated common marmosets. 1090 26

Recent reports describe the detection of high titres of antibodies to glutamic acid decarboxylase (GAD-Ab) in the serum and cerebrospinal fluid (CSF) of patients with cerebellar ataxia. Most of these cases are females with Polyglandular Autoimmune Disorder who develop a chronic cerebellar syndrome. The CSF profile is in keeping with an autoimmune disorder and intrathecal GAD-Ab synthesis has been demonstrated. The ataxia could reverse after immunomodulatory treatments suggesting a possible pathogenetic role for GAD-Ab.
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PMID:Cerebellar ataxia associated with anti-glutamic acid decarboxylase autoantibodies. 1288 38

Immunological derangement is assumed to be present in a subgroup of patients affected by drug-resistant epilepsy with serum harboring anti-glutamic acid decarboxylase autoantibodies (GAD-Ab). To further investigate the specific reactivity of GAD-Ab with target cells, we tested sera from drug-resistant epileptics harboring GAD-Ab on cultured fetal rat hippocampal neurons. As a control, we tested sera from GAD-Ab-negative epileptics and GAD-Ab-positive patients affected by Stiff Person Syndrome (SPS), ataxia or diabetes. A specific pattern of reactivity, varying according to disease, was detected on application of sera from GAD-Ab-positive patients with epilepsy, SPS and ataxia, but no specific labeling was found on application of sera from patients with GAD-Ab-negative epilepsy or from GAD-Ab-positive diabetic controls.
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PMID:Peculiar labeling of cultured hippocampal neurons by different sera harboring anti-glutamic acid decarboxylase autoantibodies (GAD-Ab). 1689 Sep 38

In slowly progressive cerebellar atrophy, it has been difficult to suppress the progression of cerebellar symptoms because no effective therapeutic agents are available when the diagnosis of secondary cerebellar atrophy, such as drug-induced cerebellar atrophy or paraneoplastic syndrome, is denied. However, amongst the different forms of slowly progressive cerebellar atrophy, some may be associated with treatable immune abnormalities. Therefore, we investigated the therapeutic efficacy of intravenous immunoglobulin (IVIg) in 9 patients with slowly progressive cerebellar atrophy (4 sporadic atrophy; 5 hereditary atrophy). The results were as follows. With regard to the 4 cases of sporadic atrophy, gait ataxia and imbalance were markedly improved in 1 patient who had positive anti-GAD antibody. Moderate improvement was seen in 1 patient and slight improvement in 2. With regard to the 5 cases of hereditary atrophy, gait ataxia and imbalance were moderately improved in 2 patients with SCA3, although there were 3 non-responders. In conclusion, our study results suggested that not only patients with sporadic atrophy but also some with hereditary atrophy may respond to therapy. In cases of slowly progressive cerebellar atrophy in which the cause may be due to immune abnormality, we should consider instituting active immunotherapy when a pathological state caused by immune abnormality is suspected after extensive evaluations of autoantibodies, including anti-GAD, anti-thyroid and anti-gliadin antibody, malignancy, and so on.
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PMID:[Efficacy of intravenous immunoglobulin for slowly progressive cerebellar atrophy]. 1706 99

"Gluten sensitive" neurological syndromes (ataxia, peripheral neuropathy, and other conditions) have been hypothesised in patients with various idiopathic neuropathologies, detectable anti-gliadin antibodies and HLA-DQ2 or DQ7. Further investigation of these cases has suggested a high incidence of anti-neuronal antibodies (anti-Purkinje, anti- neuronal nuclear, anti-GAD). This study investigates this contentious area. Over a two-year period, from a local UK population base of two million, seeing over 5000 general neurology referrals per year, we collected 20 cases with idiopathic ataxia, and 32 with idiopathic peripheral neuropathy, and referred them all for blinded antibody testing. 30 adult healthy blood donors, and 7 cases of hereditary ataxia were used as control subjects. Anti-gliadin antibodies (IgG and or IgA) were found in 40% of cases with idiopathic ataxia, 34% with idiopathic peripheral neuropathy, 17% healthy blood donors and 43% with hereditary ataxia. None was positive for antiPurkinje cell or anti-neuronal nuclear antibodies. Only two patients with idiopathic ataxia were positive for antiGAD antibodies (one also being anti-gliadin positive). We were unable to confirm the findings of other groups. First, cases of so-called "gluten sensitive" neurological syndromes were extremely rare in our centre. Second, our idiopathic cases, whether they be gliadin antibody seropositive or not (i.e. "gluten sensitive" or not) were rarely neuronal autoantibody positive.
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PMID:Cerebellar ataxia, peripheral neuropathy, "gluten sensitivity" and anti-neuronal autoantibodies. 1717 89

Opsoclonus-myoclonus-ataxia syndrome (OMS) is a rare neurological disorder of probably autoimmune origin. Most cases are associated with a remote neoplasm or a viral infection; however in some instances no underlying aetiology can be demonstrated. We report the presence of anti-glutamic acid decarboxylase antibodies (anti-GAD Abs) in the serum and CSF of a patient with idiopathic OMS. Treatment with intravenous immunoglobulin led to a remarkable clinical improvement with parallel reduction of anti-GAD titers. Anti-GAD Abs have been associated with several neurological syndromes. They could also be responsible for the clinical triad of OMS, by impairing GABAergic transmission in specific brainstem and cerebellar circuits. We propose that testing for anti-GAD Abs should be performed in OMS, especially when no other aetiological association can be demonstrated.
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PMID:Opsoclonus-myoclonus-ataxia syndrome with autoantibodies to glutamic acid decarboxylase. 1843 86

We present the case of a 51-year-old man with a 5-year history of slowly progressive gait ataxia and dysarthria who showed a wide-based gait requiring assistance. The patient's score on the Revised Hasegawa Dementia Scale (HDS-R) was 22/30 and constructional apraxia was also evident. Cerebrospinal fluid analysis showed 3 cells/microl, and the protein concentration was 58 mg/dl. Brain MRI showed no evidence of cerebellar atrophy, and SPECT-eZIS showed no decrease in cerebellar blood flow. However, voxel based morphometry (VBM) and FineSRT revealed cortical cerebellar atrophy and reduced cerebellar blood flow. In addition, the patient tested positive for anti-gliadin (IgA) and anti-SS-A/Ro antibodies, and was thus diagnosed as having autoimmune cerebellar ataxia. The patient showed positive response to intravenous immunoglobulins (IVIg) and regained the ability to walk unassisted. The HDS-R score also improved to 27/30. If cortical cerebellar atrophy can be diagnosed in the early stages in patients with progressive cerebellar ataxia by imaging techniques such as MRI-VBM and FineSRT, and if such patients test positive for anti-gliadin, anti-GAD or anti-thyroid antibodies, it is possible that they have autoimmune cerebellar ataxia. The commencement of immunotherapy including IVIg should be considered in such
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PMID:[A case of anti-gliadin-antibody-positive cerebellar ataxia effectively treated with intravenous immunoglobulin in which voxel-based morphometry and FineSRT were diagnostically useful]. 1922 95

The cerebellum, and in particular the Purkinje cells within it, appear to be a frequent immunological target in the context of some systemic diseases. This is perhaps more often the case with the cerebellum by comparison to other structures within the central nervous system. This observation may relate to the fact that the cerebellum is one of the largest, oldest, and most structurally conserved structures in the vertebrate nervous system and/or that Purkinje cells possess good and multiple antigenic targets. Immune-mediated ataxias include paraneoplastic cerebellar degeneration and post-infective cerebellitis, but these will be discussed elsewhere. This chapter covers in detail the epidemiology, clinical characteristics, pathophysiology, and treatment of some other examples of immune-mediated ataxias, including gluten ataxia and ataxia associated with anti-GAD antibodies. There is particular emphasis on gluten ataxia as this is one of the commonest immune-mediated cerebellar ataxias and one of the few ataxias that are potentially treatable. The chapter also introduces the concept of primary autoimmune cerebellar ataxia as a form of organ-specific autoimmune disease for the first time. The pathophysiology leading to cerebellar damage, loss of Purkinje cells, and the development of ataxia remains speculative, but existing clues are discussed in detail.
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PMID:Immune-mediated acquired ataxias. 2182 89


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