Clinical and electrophysiological observations in patients with myotonic muscle disease and the therapeutic effect of N-propyl-ajmalin

@article{Birnberger2004ClinicalAE,
  title={Clinical and electrophysiological observations in patients with myotonic muscle disease and the therapeutic effect of N-propyl-ajmalin},
  author={Karl L. Birnberger and Reinhardt Rüdel and Albrecht Struppler},
  journal={Journal of Neurology},
  year={2004},
  volume={210},
  pages={99-110}
}
SummarySix patients with congenital myotonia and 4 patients with myotonic dystrophy have been examined clinically before and after the administration of N-propyl-ajmalin, an alkaloid frequently used as a cardiac antiarrhythmic drug. All patients but one reported a good to moderate improvement of their myotonic muscle stiffness. This was verified by measuring the time the patients needed to ascend a flight of stairs and by recording the speed of opening the hand.The amplitude of the compound… 
Antimyotonic therapy with tocainide under ECG control in the myotonic dystrophy of curschmann-steinert
TLDR
In these patients suffering from myotonic dystrophy with typical cardiomyopathy no deleterious effects of the drug were observed, especially no cardiac arrhythmias which would have necessitated interruption of treatment, therefore, the authors recommend symptomatic therapy with tocainide for myotonia and paramyotonia congenita, as well as in myOTonic dystroke patientssuffering from markedMyotonic stiffness.
Myotonia not aggravated by cooling
TLDR
The results indicate that exposure to cold has a specific effect on muscle function only in paramyotonia and is registered the compound muscle action potential, the isometric twitch force and the time to half relaxation, the maximum tetanic force andThe time to 3/4 relaxation.
Influence of extracellular potassium and intracellular pH on myotonia
TLDR
It is concluded that although changes of extracellular K+ influence both myotonia and the warmup, these changes are unlikely to explain warmup in myotonic patients.
Repurposing of sodium channel antagonists as potential new anti-myotonic drugs
Drug treatment for myotonia.
TLDR
It is impossible to determine whether drug treatment is safe and effective in the treatment of myotonia due to insufficient good quality data and lack of randomised studies, but small single studies give an indication that clomipramine and imipramines have a short-term beneficial effect and that taurine has a long- term beneficial effect on myOTonia.
Arrhythmia exacerbation after sodium channel blockade in myotonic dystrophy type 1
TLDR
A DM1 patient who received a sodium channel blocker that exacerbated an arrhythmia is reported, and a Cochrane review concluded that it is impossible to determine whether drug treatment of myotonia is effective or safe because of the lack of high-quality studies.
Drug treatment for myotonia (Review)
TLDR
It is impossible to determine whether drug treatment is safe and effective in the treatment of myotonia due to insufficient good quality data and lack of randomised studies, but small single studies give an indication that clomipramine and imipramines have a short-term beneficial effect and that taurine has a long- term beneficial effect on myOTonia.
Preclinical pharmacological in vitro investigations on low chloride conductance myotonia: effects of potassium regulation
TLDR
In vitro results of this study suggest that increasing potassium conductivity via activation of voltage-gated potassium channels enhanced the warm-up phenomena, thereby offering a potential therapeutic treatment option for myotonia congenita.
Transient muscular weakness in severe recessive myotonia congenita
TLDR
The maximum force of voluntary muscle contraction was registered under isometric conditions in nine patients with recessive myotonia congenita in order to study the cause of transient weakness, which seems to be similar to that of myotonic stiffness.
Phenotypic variability in myotonia congenita
TLDR
The phenotype depends on the mutation type to some extent, but this does not explain the fact that severity varies greatly between heterozygous family members and may even vary with time in the individual patient.
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References

SHOWING 1-10 OF 25 REFERENCES
The Essential Mechanism in Myotonia
THE prolonged muscle contractions which characterize the myotonic syndrome have been subjected to numerous investigations, the conclusions of which have differed, even since the development of
Neurophysiologische Untersuchungen über das Stadium passagerer Lähmung bei Myotonia congenita und Dystrophia myotonica
TLDR
3 patients with myotonia congenita manifested a clearly distinguishable temporary phase of paresis directly after stimulation was begun, and probably the disturbance is due to an alteration of the muscle fibre membrane.
Therapy of myotonia;
TLDR
Diphenylhydantoin is a useful and safe compound in the management of myotonia and is concluded to be an agent which has similar pharmacologic attributes.
Myotonic Dystrophy and its Differential Diagnosis
Myotonic dystrophy (My.D.) is a rather frequent autosomal dominant heredopathy characterized by, in some instances, marked myotonia, slowly progressive skeletal muscle weakness and often, with heart
Mammalian skeletal muscle: Reduced chloride conductance in drug-induced myotonia and induction of myotonia by low-chloride solution
TLDR
All characteristic features of the myotonic reaction observed in myotonia congenita of man and goat are shown to exist in “low-chloride-myotonia”.
Muscle membrane protein kinase in myotonic muscular dystrophy
TLDR
The suggestion that myotonic muscular dystrophy is a disease resulting from a basic membrane abnormality due to phosphorylation of endogenous membrane proteins is supported.
Effects of quinidine, procaine amide, and N-propyl-ajmaline on skeletal muscle
TLDR
Membrane and action potentials of rat diaphragm fibres were measured in vitro as affected by quinidine, procaine amide, and N-propyl-ajmaline in concentrations of 10−5 to 10−4 g/ml and all drugs increased contraction time.
Protein kinase activity in erythrocyte ghosts of patients with myotonic muscular dystrophy.
  • A. Roses, S. Appel
  • Biology, Medicine
    Proceedings of the National Academy of Sciences of the United States of America
  • 1973
TLDR
A significant difference is demonstrated in the phosphorylation of erythrocyte ghost protein by [gamma-(32)P]ATP, with endogenous protein kinase of ERYthrocye membrane as the enzyme source, with a reproducible difference in normal and myotonic membranes.
Electron spin resonance studies of erythrocytes from patients with myotonic muscular dystrophy.
Electron magnetic resonance experiments have demonstrated that spin-labeled myotonic erythrocyte membranes have spectra that are recognizably different from those of normal erythrocytes. The spin
Muscular paralysis in myotonia congenita.
While examining a patient with myotonia congenita, it was found that stimulation of the ulnar nerve with frequencies of 5 or 8 cps caused the amplitude of the muscle action potential to decrease rapid
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