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Query: UMLS:C0024591 (malignant hyperthermia)
 2,353 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A member of a family which was known to be susceptible to malignant hyperpyrexia, who was identified as a carrier by the presence of an elevated serum creatine-phosphokinase, has been investigated further. Muscle was examined biochemically, and the study included the sarcoplasmic ATPase-activity, actinomycin, Mg2+ ATPase activity, ATP, phosphocreatine and glucose-6-phosphate. In addition, the calcium uptake by the sarcoplasmic reticulum was studied. The histochemical analysis of the muscle revealed the presence of a new fibre type characterised by a dense rim of ATPase activity, which gives the impression of a 'picture-frame'. Ultramicroscopic study revealed changes in the mitochondria and areas of myofibrillar disruption with swelling of the sarcoplasmic reticulum.
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PMID:'Picture frame' fibres in a carrier of the trait for malignant hyperpyrexia. 0 Jul 95

This communication presents evidence in support of a neuropathic basis for the myopathy associated with malignant hyperpyrexia (MH). Muscle from MH susceptible individuals showed a reduced calcium uptake by the sarcoplasmic reticulum. There was a reduced concentration of phosphocreatine and ATP and an increased concentration of glucose-6-phosphate in these muscle samples.
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PMID:Morphological and biochemical defects in muscles of human carriers of the malignant hyperthermia syndrome. 12 80

Vastus lateralis muscle was excised from normal pigs and from pigs susceptible to malignant hyperthermia. Anesthesia consisted of diazepam, N2O:O2, and a lidocaine field block. In the susceptible (MHS) pigs, respiratory control in mitochondria of excised muscle was normal, while electron transport was accelerated. Glutamate log Q3's and log Q4's were in inverse linear relationship to porcine weights. In the presence of glutamate, state 3 respiration was 3.5 times, and state 4 respiration 3.2 times, higher in MHS than in normal mitochondria (independent of weight or halothane dose). Thus, the MHS mitochondria were able to produce ATP more efficiently than normal mitochondria. In vitro, halothane inhibited glutamate Q3's and R.C.I.'s, slightly increased succinate Q3's and R.C.I.'s, had no significant effect on glutamate or succinate Q4's, and, moderately lowered glutamate and succinate P/O ratios. These changes were similar to those observed in normal pigs. Calcium uptake into MHS mitochondria was markedly less than normal but was not significantly altered by in-vitro halothane. These results suggest a mitochondrial membrane component for the defect of procine malignant hyperthermia since calcium is normally associated with the formation of the phospholipid lattice of this membrane. (Key words: Hyperthermia, malignant; Metabolism, mitochondrial; Muscle, skeletal, mitochondria; Anesthetics, volatile, halotbane; Ions, calcium.)
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PMID:Porcine malignant hyperthermia: effects of halothane on mitochondrial respiration and calcium accumulation. 16

MHS and normal pigs were anaesthetized with nitrous oxide and diazepam. Halothane 1% was then administered for 1 hr. Immediately before and immediately after the halothane inhalation, 10 g of vastus lateralis muscle was excised. SR was isolated from this muscle. Calcium accumulation by the MHS sarcoplasmic reticulum in the absence of halothane was greater than normal. Halothane in vitro produced a similar increase in calcium uptake into both the MHS and the normal SR. Halothane in vivo significantly reduced calcium accumulation by hyperthermic SR but had no significant effect on calcium uptake into the normal SR. Thus the action of halothane on the MHS sarcoplasmic reticulum is indirect, occurring only in the intact cell. It is possibly a result of the deleterious effect which lack of ATP, a low pH or a high temperature is likely to have on the calcium accumulating mechanism of the SR membrane. Our results suggest that the primary defects of porcine and human malignant hyperthermia are not entirely synonymous.
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PMID:Calcium uptake into muscle of pigs susceptible to malignant hyperthermia: in vitro and in vivo studies with and without halothane. 23 50

Malignant hyperpyrexia is a genetically related syndrome that cannot be predicted reliably in advance of administration of anesthesia except by a strong family history. The definitive etiology is unknown, although triggering agents that release calcium from the calcium-storing sarcoplasmic membrane of the muscle cell are highly suspect. As soon as the syndrome is diagnosed, therapy must be prompt, vigorous, and carried out with the same urgency as a cardiac arrest. Specific therapy with dantrolene sodium may prove to be an answer to this serious problem in anesthetic practice.
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PMID:Malignant hyperpyrexia. 32 54

Malignant hyperthermia may appear during surgery. It has at least three features: 1) an anesthesiological trigger, usually the association of halothane and succinylcholine; 2) rapid increase in body temperature; 3) widespread muscle hypertonia. The literature is reviewed in an assessment of the physiopathological mechanism underlying the syndrome, with particular reference to the part played by calcium. Experimental data are cited and their similarity with the clinical, laboratory, anatomical, and histopathological picture in man is discussed. A detailed account is also given of two personal cases. Lastly, questions associated with the prevention and treatment of malignant hyperthermia are examined.
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PMID:[Malignant hyperthermia. Review of literature and case reports]. 39 55

Some non-rigid Malignant Hyperthermia Susceptible (MHS) patients have a greater than normal incidence of fractures. Radiologically their long bones are slightly thinner than normal. Excessive numbers of caries because of thin dental enamel may also be present. The Malignant Hyperthermic (MH) defects thus appears to involve cells of bone appendages as well as of muscle. We have measured the concentration of calcium in bone by neutron activation analysis and have found it to be reduced in both non-rigid and rigid malignant hyperthermia susceptible patients. The reductions were particularly marked for the non-rigid patients. Bone calcium concentrations were lower in males than in females and in those under 16 and over 60 years of age. This is additional evidence is favour of the hypothesis that malignant hyperthermia is a widespread defect affecting tissues and organs throughout the body.
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PMID:In vivo neutron activation analysis for bone calcium (INVAA) in malignant hyperthermia susceptible patients. 46 46

The effects of varying temperatures from 25 degrees to 37 degrees C on calcium binding characteristics of sarcoplasmic reticulum from malignant hyperthermia-susceptible (MHS) and control pig muscle were examined. Two groups of MHS pigs were included: those with high susceptibility to malignant hyperthermia (MHS group) and a cross-bred, less susceptible group (MHX). At 25 degrees C, calcium binding was lower for MHS than for controls and MHX. As temperature was increased by 2 degrees C jumps, calcium binding decreased in all sarcoplasmic reticulum fractions. At 35 degrees C a sharp decrease in calcium binding occurred in the MHS and MHX fractions. The sharp decrease in calcium binding at 35 degrees C differentiated the MHS and MHX fractions from controls. The initial velocity (Vi) for calcium binding was lower in MHS fractions between 25 degrees and 35 degrees C when compared with MHX and controls. All fractions had increased Vi values as temperature increased from 25 degrees to 35 degrees C. From 35 degrees to 39 degrees Vi for controls increased markedly. In contrast, Vi for the MHX fraction decreased as temperature exceeded 35 degrees C. These temperature effects on calcium binding characteristics of sarcoplasmic reticulum from MHS and MHX muscle may be indicative of a membrane transition that impairs calcium binding.
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PMID:Temperature perturbation studies of sarcoplasmic reticulum from malignant hyperthermia pig muscle. 47 74

To examine the function of sarcoplasmic reticulum (SR) in malignant hyperthermia, SR was isolated from semitendinosus muscle of normal and genetically susceptible Poland China swine. Determinations included rate of calcium binding (oxalate absent), rate and capacity of calcium uptake (oxalate present), and spontaneous calcium release (in the absence of ionic depolarization or calcium) with and without halothane, using the millipore filtration technique. Rate of calcium binding, and rate and capacity of calcium uptake were decreased, and spontaneous calcium release was greater in SR fragments from susceptible swine as compared to those from normal swine. Halothane 0.5% slightly increased the rate of calcium binding in susceptible and normal SR. Above 1%, halothane decreased calcium binding rate, and uptake rate and capacity, and increased calcium release similarly in susceptible and normal SR. These differences in SR function were insufficient to explain the etiology of malignant hyperthemia, nor did the effect of halothane account for its triggering action.
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PMID:Skeletal muscle sarcoplasmic reticulum in porcine malignant hyperthermia. 49 49

We describe a development of a malignant hyperthermia (MH) syndrome, partially aborted by therapy, in a child with central core disease and congenital dislocating hips. Patients with central core disease appear to be more susceptible to MH; possibly those with elevated serum creatine phosphokinase levels, as in our patient, are especially susceptible. We review the clinical and pathologic aspects, possible pathogenesis, and treatment of the MH syndrome. An increased calcium level within the muscle fiber is suggested as the major cytodestructive factor, and that increase could be consequent to a plasmalemmal susceptibility to the provoking drugs hypothesized to be the basic defect in MH. Prevention of the full manifestations of MH is predicated on (1) a high index of suspicion in the search for history of anesthetic complications in the patient and his family, with or without evident neuromuscular disease, (2) recognition that there is a somewhat greater risk of MH developing in a patient who has certain "musculoskeletal" abnormalities or muscle weakness but that is not-except for central core disease-a classic clinicopathologically defined disease, (3) close monitoring of patients during anesthesia, and (4) if the syndrome develops, prompt therapeutic measures, including cessation of anesthesia.
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PMID:Malignant hyperthermia and central core disease in a child with congenital dislocating hips. 63 52


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