Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026850 (muscular dystrophy)
 5,870 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The number of putative calcium channels in cardiac muscle from young adult hamsters (60 days old) was compared in normal (F1B) hamsters and two different mutant strains (CHF 146 and Bio 14.6) which express cardiomyopathy and muscular dystrophy. Equilibrium binding assays of high affinity sites for [3H]-nitrendipine in ventricular homogenate preparations showed that the maximum number of [3H]-nitrendipine binding sites (Bmax), which corresponds to the number of putative calcium channels, was not significantly different in normal and cardiomyopathic hearts: 79(SEM 9), 64(14) and 69(10) fmol.mg-1 protein in 4-6 hearts from F1B, Bio 14.6 and CHF 146 hamster strains, respectively. Similar results were obtained with binding data after partial purification of the preparation. These data are in agreement with earlier studies comparing two normal strains (CHF 148 and random bred Syrian hamsters) with cardiomyopathic (CHF 146) hamsters, and conflict with other studies comparing normal and cardiomyopathic hamsters. Comparisons with the conflicting data suggest (a) that change in the number of high affinity [3H]-nitrendipine binding sites is not responsible for calcium overload and cell necrosis in cardiomyopathy, and (b) that increased numbers of low affinity [3H]-nitrendipine binding sites may emerge in cardiomyopathic hearts.
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PMID:[3H]-nitrendipine binding sites in normal and cardiomyopathic hamsters: absence of a selective increase in putative calcium channels in cardiomyopathic hearts. 285 22

Dimethyl-4, 4'-dimethoxy-5, 6, 5'-6'-dimethylenedioxybiphenyl-2, 2'-dicarboxylate (DDB) is a synthetic analogue of Schizandrin C, an active compound isolated from a Chinese herb, Fructus schizandrae. We administered this compound to dystrophic hamsters in vivo for 31 days. This led to a 61% reduction of the calcium content, an 86% reduction of the area of calcium deposits, and a 52% reduction of the area of necrosis of cardiac muscle. However, skeletal muscle necrosis was not significantly improved. No clear change in plasma creatine kinase (CK) was observed. In an in vitro incubation study, the rate of CK release and tetanus tension of the extensor digitorum longus muscle of dystrophic hamsters were not substantially changed by the addition of DDB. This study suggests that DDB has some effect on cardiac necrosis, and that it might be useful for treatment of the cardiac involvement in patients with muscular dystrophy or other conditions with accompaning Ca accumulation.
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PMID:The effect of DDB on dystrophic hamsters: an in vivo and in vitro study. 361 53

The present study was undertaken to elucidate further the enzymatic changes in dystrophic muscle using multivariate analysis. The activities of 14 kinds of enzymes, including 6 exopeptidases, 4 endopeptidases, beta-N-acetyl-D-glucosaminidase, phosphatase, esterase, and ribonuclease, were examined in forelimb and hindlimb muscles as well as in cardiac muscle of dystrophic mice and their controls. Two principal components identified from the enzymatic spectrum proved to be related especially to aminopeptidases and to serine proteinases, respectively. The enzymatic changes in forelimb muscle were very similar to those in hindlimb muscle when both were compared to those in cardiac muscle. The changes in aminopeptidases were unique to the limb muscles, whereas those of serine proteinases were unique to cardiac muscle of dystrophic mice. In the future, more attention should be focused on the role of exopeptidases in pathogenetic mechanisms of muscular dystrophy, because of the possibility that they play a major role in the initial stage of muscular dystrophy.
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PMID:A multivariate study on enzymatic changes in limb muscles and heart muscle of dystrophic mice. 367 74

The intramembrane particle (IMP) profile of control and dystrophic (Bio 14.6) hamster cardiac muscle plasma membrane was assessed in freeze-fracture replicas to determine whether this animal model of muscular dystrophy exhibits the same membrane characteristics found in skeletal muscle from other more thoroughly studied dystrophic animals, and to test the hypothesis that the plasma membrane of the cardiac muscle cell is the site of a defect associated with the disease. Samples of cardiac muscle tissue from hamsters ranging in age from 1 to 13 months were freeze-fractured. Intramembrane particle numbers were determined for all tissue samples by counting randomly selected areas of P- and E-face surfaces. Up to the age of 1 month, the particle density was the same in both strains of hamster, after which time, the population of IMPs was about 30% lower in dystrophic than in normal heart sarcolemma. This 30% difference in particle frequency in dystrophic hamster heart membrane is consistent with values published for cell membrane from other muscular dystrophies and supports the theory that there is a defect in the plasma membrane of dystrophic cells. In addition, this study has shown for the first time that a presumed membrane defect related to muscular dystrophy (reduced number of IMPs) may be present throughout the life of the animal (1-13 months), and expressed in every cell sampled.
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PMID:A freeze-fracture analysis of intramembrane particle densities on dystrophic hamster heart sarcolemma. 654 70

Adhalin is deficient in two forms of human muscular dystrophy, one due to mutations in the adhalin gene and one linked to an unidentified gene on chromosome 13. Because adhalin is deficient in skeletal and cardiac muscles of BIO 14.6 hamsters, which experience both myopathy and cardiomyopathy, cDNA encoding adhalin from BIO 14.6 hamster skeletal muscle was cloned and sequenced. Adhalin mRNA was expressed at normal levels in BIO 14.6 hamster cardiac muscle, and no mutation in adhalin coding sequence was found, indicating that the inherited myopathy and cardiomyopathy of the BIO 14.6 hamster are most likely not due to mutations in the adhalin gene.
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PMID:Adhalin mRNA and cDNA sequence are normal in the cardiomyopathic hamster. 775 76

Cardiac involvement in congenital muscular dystrophy (CMD) has not previously been reported in the literature excepting Japanese ones. The purpose of this study was to investigate the probability of cardiac muscle involvement in 25 patients with CMD. Left ventricular dimensions, wall thicknesses and function were investigated by M-mode and Doppler echocardiography in patients and healthy control subjects. The M-mode echocardiographic data were similar in the two groups. However, the left ventricular mass index in the study group was significantly lower than that of the control group. Left ventricular diastolic function also differed significantly when compared with that of the control group. Mild diastolic dysfunction of the left ventricle might precede manifestations of probable cardiac muscle involvement or subclinical cardiac involvement.
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PMID:Left ventricular structure and function by echocardiography in congenital muscular dystrophy. 781 25

Merosin is the predominant laminin isoform in the basal lamina of striated muscle and peripheral nerve, and consists of M, B1 or S, and B2 chains. Here we have demonstrated that merosin is a native ligand for alpha-dystroglycan, an extracellular component of the dystrophin-glycoprotein complex. We have also mapped the mouse M chain gene, Lamm, to the same region of mouse chromosome 10 to which the dystrophia muscularis (dy) locus has been mapped. The dy mutation represents a severe neuromuscular disease resembling human muscular dystrophy. Analysis of merosin expression of dystrophic dy mice revealed a specific deficiency of merosin in skeletal muscle, cardiac muscle, and peripheral nerve. Our results indicate that merosin deficiency may be the primary defect in dy mice and suggest that a disruption of the link between alpha-dystroglycan and merosin may be involved in the pathogenesis of muscle degeneration and peripheral neuropathy in dy mice.
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PMID:Deficiency of merosin in dystrophic dy mice and genetic linkage of laminin M chain gene to dy locus. 818 45

A 47-year-old woman whose elder son had typical Duchenne's muscular dystrophy (DMD) was diagnosed as the manifesting carrier of the disease. She had developed congestive heart failure but had no evidence of skeletal muscular atrophy. Histological observation of the cardiac muscle revealed a mosaic pattern of dystrophin negative fibres detected by immunofluorescence analysis.
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PMID:Dystrophin negative skeletal and myocardial muscle cells in a carrier of Duchenne's muscular dystrophy. 837 25

Identification of the defective gene and the absent gene product dystrophin can substantiate the clinical evidence for manifesting X-linked Duchenne type muscular dystrophy (DMD). It is not always possible, however, to rule out definitely a clinically asymptomatic carrier status in question, since even in the proven carrier DNA analysis is often inconclusive, and multinucleated skeletal muscle fibers express a basically normal membrane dystrophin. To substantiate the value of endomyocardial biopsy as a new tool for detection of the DMD carrier status we examined an endomyocardial biopsy of a volunteer who met the clinical criteria of a DMD carrier. Dystrophin immunohistochemistry and western blot of her skeletal muscle biopsy were inconclusive, and polymerase chain reaction and cDNA analysis failed to locate directly the X-chromosomal defect. We observed a clearcut mosaic of dystrophin-positive and -negative mononucleated cardiac muscle cells, reflecting a heterozygote carrier status in her endomyocardial biopsy, whereas 20 controls were uniformely positive. The incidence of DMD (1:3000 males) and especially the 30% spontaneous mutation rate, still the major pitfall in DNA analysis, show the need for an additional diagnostic tool.
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PMID:Heterozygotic gene expression in endomyocardial biopsies: a new diagnostic tool confirms the Duchenne carrier status. 848 29

Duchenne's muscular dystrophy (DMD) is a common X-linked neuromuscular disease which predominantly affects skeletal and cardiac muscle. The absence of dystrophin, the metabolic defect that causes DMD, leads to a peculiar cardiomyopathy which initially affects the posterior wall of the left ventricle. We review evidence that dystrophin deficient myocytes become dystrophic in order of increasing axial stress upon the myocyte. Thus, dystrophin's function may be that of physically reinforcing the sarcolemma against the axial forces exerted upon the myocyte.
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PMID:The cardiomyopathy of Duchenne's muscular dystrophy and the function of dystrophin. 850 96


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