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Corrêa S, Basso RM, Cerri FM, de Oliveira‐Filho JP, Araújo JP, Torelli SR, Salán LPCDC, Salán MO, Macedo IZ, Borges AS. Hereditary myotonia in cats associated with a new homozygous missense variant p.Ala331Pro in the muscle chloride channel ClC-1. J Vet Intern Med 2023; 37:2498-2503. [PMID: 37668104 PMCID: PMC10658498 DOI: 10.1111/jvim.16837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 08/16/2023] [Indexed: 09/06/2023] Open
Abstract
Three-related cats were evaluated for a history of short-strided gait and temporary recumbency after startle. Neurological examination, electromyography (EMG), muscle biopsies, and a chloride voltage-gated channel 1 (CLCN1) molecular study were performed. Clinically, all 3 cats presented myotonia with warm-up phenomenon and myotonic discharges during EMG examination. Muscle biopsies showed normal muscle architecture and variation in the diameter of myofiber size with the presence of numerous hypertrophic fibers. The molecular study revealed a missense variant (c.991G>C, p.Ala331Pro) in exon 9 of the CLCN1 gene, responsible for the first chloride channel extracellular loop. This mutation was screened in 104 control phenotypically normal unrelated cats, and all were wildtype. The alanine at this position is conserved in ClC-1 (chloride channel protein 1) in different species, and 2 mutations at this amino acid position are associated with human myotonia. This is the third CLCN1 mutation described in the literature associated with hereditary myotonia in cats and the first in domestic animals located in an extracellular muscle ClC-1 loop.
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Affiliation(s)
| | - Roberta Martins Basso
- School of Veterinary Medicine and Animal Science, São Paulo State University (UNESP)BotucatuSão PauloBrazil
| | - Fabricio Moreira Cerri
- School of Veterinary Medicine and Animal Science, São Paulo State University (UNESP)BotucatuSão PauloBrazil
| | | | - João Pessoa Araújo
- Institute of Biotechnology (IBTEC), São Paulo State University (UNESP)BotucatuSão PauloBrazil
| | | | | | | | | | - Alexandre Secorun Borges
- School of Veterinary Medicine and Animal Science, São Paulo State University (UNESP)BotucatuSão PauloBrazil
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YOKOTA S, KOBATAKE Y, MAEKAWA M, TAKASHIMA S, NISHII N. Trismus due to myotonia associated with hyperadrenocorticism in a dog. J Vet Med Sci 2023; 85:876-879. [PMID: 37357395 PMCID: PMC10466053 DOI: 10.1292/jvms.23-0103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 05/31/2023] [Indexed: 06/27/2023] Open
Abstract
We present the report of trismus due to hyperadrenocorticism-associated myotonia diagnosed by electromyography in a dog. An intact female Miniature Dachshund, 13 years and 9 months old, presented with stiff gait and trismus as well as polyuria and polydipsia. Abdominal ultrasonography showed enlarged adrenal glands. An adrenocorticotropic hormone stimulation test revealed an exaggerated response. Based on these findings, this case was diagnosed with hyperadrenocorticism. Electromyography revealed myotonic discharge in the temporalis muscle and limbs. Therefore, trismus was considered to be caused by hyperadrenocorticism-associated myotonia, and the case was treated with oral trilostane (1.3 mg/kg, once daily). During the 4-month follow-up period, despite the partial improvement in stiff gait, trismus did not recover. Long-term data on more cases are warranted to assess the prognosis and clinical characteristics of trismus due to hyperadrenocorticism-associated myotonia.
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Affiliation(s)
- Shunya YOKOTA
- Joint Graduate School of Veterinary Sciences, Gifu
University, Gifu, Japan
| | - Yui KOBATAKE
- Joint Department of Veterinary Medicine, Faculty of Applied
Biological Science, Gifu University, Gifu, Japan
| | | | - Satoshi TAKASHIMA
- Joint Department of Veterinary Medicine, Faculty of Applied
Biological Science, Gifu University, Gifu, Japan
| | - Naohito NISHII
- Joint Graduate School of Veterinary Sciences, Gifu
University, Gifu, Japan
- Joint Department of Veterinary Medicine, Faculty of Applied
Biological Science, Gifu University, Gifu, Japan
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Chimenes ND, Caramalac SM, Caramalac SM, Fernandes TD, Basso RM, Cerri FM, Oliveira-Filho JP, Borges AS, Palumbo MIP. A complex CLCN1 variant associated with hereditary myotonia in a mixed-breed dog. J Vet Diagn Invest 2023; 35:413-416. [PMID: 37212506 PMCID: PMC10331391 DOI: 10.1177/10406387231176736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/23/2023] Open
Abstract
Hereditary myotonia (HM) is characterized by delayed muscle relaxation after contraction as a result of a mutation in the CLCN1 gene. We describe here a complex CLCN1 variant in a mixed-breed dog with clinical and electromyographic signs of HM. Blood samples from the myotonic dog, as well as from his male littermate and parents, were analyzed via amplification of the 23 exons encoding CLCN1. After sequencing the CLCN1 gene, a complex variant was found in exon 6 c.[705T>G; 708del; 712_732del], resulting in a premature stop codon in exon 7 and a protein that was 717 amino acids shorter than the normal CLC protein. The myotonic dog was identified as homozygous recessive for the complex CLCN1 variant; its parents were heterozygous, and its male littermate was homozygous wild-type. Knowledge of the CLCN1 mutations responsible for the development of hereditary myotonia allows greater clarification of this condition.
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Affiliation(s)
- Natielly D. Chimenes
- Faculty of Veterinary Medicine and Animal Science, Federal University of Mato Grosso do Sul (UFMS), Campo Grande, Mato Grosso do Sul, Brazil
| | - Silvana M. Caramalac
- Faculty of Veterinary Medicine and Animal Science, Federal University of Mato Grosso do Sul (UFMS), Campo Grande, Mato Grosso do Sul, Brazil
| | - Simone M. Caramalac
- Faculty of Veterinary Medicine and Animal Science, Federal University of Mato Grosso do Sul (UFMS), Campo Grande, Mato Grosso do Sul, Brazil
| | - Thiago D. Fernandes
- Faculty of Veterinary Medicine and Animal Science, Federal University of Mato Grosso do Sul (UFMS), Campo Grande, Mato Grosso do Sul, Brazil
| | - Roberta M. Basso
- Department of Veterinary Clinical Science, School of Veterinary Medicine and Animal Science, São Paulo State University (Unesp), Botucatu, São Paulo, Brazil
| | - Fabrício M. Cerri
- Department of Veterinary Clinical Science, School of Veterinary Medicine and Animal Science, São Paulo State University (Unesp), Botucatu, São Paulo, Brazil
| | - José P. Oliveira-Filho
- Department of Veterinary Clinical Science, School of Veterinary Medicine and Animal Science, São Paulo State University (Unesp), Botucatu, São Paulo, Brazil
| | - Alexandre S. Borges
- Department of Veterinary Clinical Science, School of Veterinary Medicine and Animal Science, São Paulo State University (Unesp), Botucatu, São Paulo, Brazil
| | - Mariana I. P. Palumbo
- Faculty of Veterinary Medicine and Animal Science, Federal University of Mato Grosso do Sul (UFMS), Campo Grande, Mato Grosso do Sul, Brazil
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Abstract
BACKGROUND Heritable myotonia is a genetic muscle disorder characterized by slow relaxation of skeletal muscles. The main clinical signs are skeletal muscle stiffness, especially after vigorous contraction, and muscle hypertrophy. Muscle stiffness may be enhanced by inactivity, and often is relieved by exercise. Myotonia can be inherited in an autosomal dominant or recessive manner (Thomsen- or Becker-type myotonia, respectively). In mice, goats, Miniature Schnauzer dogs, and most affected humans, the disorder is caused by mutations in CLCN1, which encodes the skeletal muscle voltage-gated chloride channel, Cl1C-1. HYPOTHESIS We hypothesized that an Australian Cattle Dog with generalized muscle stiffness and hypertrophy examined at the Ontario Veterinary College would have a mutation in the CLCN1 gene. ANIMALS A pure-bred Australian Cattle Dog from Ontario, Canada, was used. METHODS Based on clinical signs and electromyographic test results, a diagnosis of myotonia hereditaria was made, and a muscle biopsy was collected for genetic analysis. RESULTS Sequence data obtained from the affected dog confirmed that it was homozygous for a single base insertion in the CLCN1 coding sequence. This mutation would result in a truncated ClC-1 protein being expressed, which, based on molecular evidence from other studies, would result in functionally compromised chloride conduction in the skeletal muscles of the animal. CONCLUSIONS AND CLINICAL IMPORTANCE To the authors' knowledge, this report describes the Ist case of myotonia in an Australian Cattle Dog and represents the 1st non-Schnauzer canine myotonia to be genetically characterized. In addition, we developed a polymerase chain reaction-based genetic screen to detect heterozygotes with this mutation in the at-large Australian Cattle Dog population.
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Affiliation(s)
- Daniel F Finnigan
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario, Canada
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Abstract
Altered excitability of the skeletal muscle membrane (sarcolemma) can result in clinical signs of muscle dysfunction. Hyperexcitability of the sarcolemma results in myotonia, and hypoexcitability results in paresis or paralysis. Our understanding of the physiologic and molecular bases of disorders of sarcolemmal excitability is rapidly increasing as techniques for evaluation are improved. This article reviews muscle excitability disorders in dogs and cats and their pathogenesis.
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Affiliation(s)
- Charles H Vite
- Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia 19104, USA.
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Abstract
OBJECTIVES To describe a case of equine muscular dystrophy with myotonia. METHODS A 5-year-old horse presented with hypertrophy and delayed relaxation of the muscles of the hindlimbs from age 2 months. Testicular atrophy developed from 2 years of age. Action and percussion myotonia was associated with weakness in these muscles, and EMG showed diffuse myotonic discharges and myopathic features. Biopsy of the gluteal muscle showed adipose and connective tissue infiltration, marked variation in muscle fibre size, and moth-eaten, ring and whorled fibres. RESULTS Injection of apamin, a peptide blocker of calcium-activated potassium channels, which inhibits myotonia in human myotonic dystrophy, was ineffective in blocking myotonic discharges. Discharges promptly abated with 2% lidocaine injection. CONCLUSIONS Myotonia in this horse is associated with dystrophic changes similar to human myotonic dystrophy, though there are some pharmacological differences.
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Affiliation(s)
- P Montagna
- Institute of Clinical Neurology, University of Bologna Medical School, Via U. Foscolo 7, 40123, Bologna, Italy.
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Abstract
Two dogs developed a disabling gait abnormality characterised by stiffness. The abnormality was consistent with a diagnosis of myotonia secondary to hyperadrenocorticism. The first dog had iatrogenic hyperadrenocorticism, and its signs improved substantially after corticosteroid administration was gradually withdrawn. The second had pituitary-dependent hyperadrenocorticism, but myotonic signs progressed despite effective mitotane therapy. Procainamide administration reduced the myotonic stiffness in the second case.
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Affiliation(s)
- G R Swinney
- Department of Veterinary Clinical Sciences, University of Sydney, New South Wales
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Vite CH, Cozzi F, Rich M, Klide AK, Volk SW, Lombardo R. Myotonic myopathy in a miniature Schnauzer: case report and data suggesting abnormal chloride conductance across the muscle membrane. Vet Med (Auckl) 1998; 12:394-7. [PMID: 9773418 DOI: 10.1111/j.1939-1676.1998.tb02141.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- C H Vite
- Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia 19104-6010, USA.
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Harrington ML, Moore MP, Talcott PA, Bagley RS, Sandmeier P. Suspected herbicide toxicosis in a dog. J Am Vet Med Assoc 1996; 209:2085-7. [PMID: 8960192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
An 8-year-old 38-kg spayed female Golden Retriever was admitted for vomiting, signs of abdominal pain on palpation, ataxia, anorexia, and generalized weakness of 2 days' duration. Ten hours prior to onset of clinical signs, the dog was found standing in and drinking from large pools of an accidentally spilled herbicide that contained an octanoic acid ester of bromoxynil (3,5-dibromo-4-hydroxybenzonitrile) and an isooctyl ester of (2-methyl-4-chloro) phenoxyacetic acid (MCPA). Appendicular muscles were firm on palpation and persistent muscle contraction (myotonia > 1 minute duration) was found on muscle percussion, using a reflex hammer. Electrical activity indicative of myotonia was identified on electromyographic evaluation. With supportive treatment, the dog eventually recovered from suspected MCPA toxicosis. Although rare, MCPA toxicosis should be considered as a cause of acquired myotonia in dogs.
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Affiliation(s)
- M L Harrington
- Department of Clinical Sciences, Washington State University, College of Veterinary Medicine, Pullman 99164-6610, USA
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Abstract
A 16-week-old, male cocker spaniel suffering from pelvic-limb "bunny hopping" as well as rigidity, spasticity, and ataxia in all limbs was evaluated. The clinical features, electrophysiological abnormalities, and muscle histopathological and histochemical evaluations led to a diagnosis of congenital myotonia. Myotonia is a disorder of skeletal muscle characterized by delayed relaxation of the muscle fiber in response to voluntary, mechanical, or electrical stimulation. The pathophysiology of congenital myotonia remains controversial; currently proposed pathomechanisms are discussed. To the authors' knowledge, this is the first case of congenital myotonia reported in a cocker spaniel.
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Affiliation(s)
- S L Hill
- San Diego Veterinary Referral Services, California 92108, USA
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Braga IS, Tanaka S, Kimura T, Itakura C, Mizutani M. Inherited muscular disorder in mutant Japanese quail (Coturnix coturnix japonica): relationship between the development of muscle lesions and age. J Comp Pathol 1995; 113:131-43. [PMID: 8543670 DOI: 10.1016/s0021-9975(05)80028-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The progression of the pathological changes that occur in the skeletal muscle was examined in 19 Japanese quail of the LWC strain, affected with an autosomal dominant inherited muscular disorder producing electrical myotonia. The muscle samples were obtained every 10 days from 20 to 70 days of age. Muscle samples from 18 age-matched commercial quail were used as normal controls. Characteristic histological lesions found in the skeletal muscles included sarcoplasmic masses, ringed fibres, internal migration of nuclei and fibre size variation. These lesions, which mainly occurred in the proximal muscles, appeared first in the pectoral region and later in the muscles of the thoracic and pelvic limbs. The most predominant lesion observed at all ages consisted of sarcoplasmic masses. The presence of histological changes did not affect muscle fibre typing by two staining methods, for myosin ATPase at pH 4.5, and by NADH-TR stain. The histological changes were observed in type 2A and less commonly in 2B fibres, but not in type 1. The pectoralis thoracicus muscle, in which lesions were particularly common, showed abnormally large type 2B muscle fibres at 20 days of age. These fibres began to decrease in size at 30 days of age, and at 70 days had become strikingly atrophic, their diameter being only about half that observed at 20 days. The atrophic type 2B muscle fibres were eventually replaced by lipocytes. Chronological staging of the histopathological changes in muscle was impossible since no inter-relationship was observed between the age of the quail, the severity of clinical signs and the extent of muscle lesions. This variability in the severity and age of onset may have been due to the variable expression or incomplete penetrance of the defective gene. Because the disorder is hereditary and progressive in nature, it can be classified as a type of progressive muscular dystrophy.
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Affiliation(s)
- I S Braga
- Department of Comparative Pathology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan
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Abstract
The pathological genetic defects in the inherited myotonias and periodic paralyses were recently elucidated using molecular genetic studies. These disorders are usually transmitted as a dominant trait from an affected parent to a child. The many clinical symptoms include cold-induced uncontrollable contraction of muscle, potassium-induced contraction and paralysis, myotonia with dramatic muscular hypertrophy, muscle stiffness, and insulin-induced paralysis (in males). Horses afflicted with the disorder can suddenly collapse, despite an impressive physique. In the past three years, these clinically defined disorders have been shown to share a common etiology: subtle defects of ion channels in the muscle-fiber membrane. Although the specific ion channel involved varies depending on the disease, most patients have single amino acid changes in the channel proteins, with both normal and mutant channels present in each muscle fiber. For each patient, we can now establish a precise molecular diagnosis in the face of overlapping clinical symptoms and begin specific pharmacological treatment based on the primary problem. These studies have also provided insight into basic muscle biology and emphasize the careful regulation of ions in muscle excitation.
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Affiliation(s)
- E P Hoffman
- Department of Molecular Genetics, University of Pittsburgh School of Medicine, Pennsylvania 15261, USA
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Beech J, Fletcher JE, Lizzo F, Johnston J. Effect of phenytoin on the clinical signs and in vitro muscle twitch characteristics in horses with chronic intermittent rhabdomyolysis and myotonia. Am J Vet Res 1988; 49:2130-3. [PMID: 3239850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
In vitro twitch characteristics of the semimembranosus muscle were evaluated in 9 clinically normal horses, in 15 horses with chronic intermittent rhabdomyolysis (CIR) and in 2 horses with myotonia. Effects of phenytoin on in vitro muscle twitch and clinical signs of CIR and myotonia were evaluated in these same horses. Times to 90% relaxation were prolonged in the horses with CIR (mean +/- SEM, 186 +/- 5.9 ms) and in 2 horses with myotonia (197 and 177 ms) compared with those in clinically normal horses (mean +/- SEM, 146 +/- 2.1 ms). Horses with CIR also had significantly (P less than 0.05) longer times to 50% relaxation, compared with clinically normal horses. In the group of horses with CIR, Standardbreds had significantly (P less than 0.05) longer times to 90% and 50% relaxation, compared with Thoroughbreds. Times to 100% peak tension did not differ among the groups. Administration of phenytoin directly into a muscle preparation bath solution had no effect on muscle twitch properties. After the initial muscle biopsy, phenytoin was administered orally for 7 to 10 days to 4 horses with CIR, 2 myotonic horses, and 2 clinically normal horses before repeat biopsy from the same site in the contralateral semimembranosus muscle. Times to 90% relaxation decreased from 197 and 177 ms to 144 and 126 ms, respectively, in the 2 myotonic horses, from a mean of 192 (+/- 9) ms to 170 (+/- 9) ms in the 4 horses with CIR and remained unchanged (154 and 140 ms before vs 155 and 139 ms after treatment) in the 2 clinically normal horses.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J Beech
- Section of Medicine, School of Veterinary Medicine, University of Pennsylvania, New Bolton Center, Kennett Square 19348
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Abstract
A severe and progressive neuromuscular disorder accompanied by clinical, electrophysiological, and pathological features resembling human dystrophia myotonica was observed in three foals. This disorder was apparent as early as 1 month of age and involved progressive skeletal muscle dysfunction, initially characterized by proximal muscle hypertrophy and hypertonicity with subsequent muscle stiffness, weakness, and atrophy. Multisystem involvement was manifested in one case by testicular hypoplasia, early cataract formation, and borderline glucose intolerance. Prolonged dimpling of these large rear-limb muscles was elicited by percussion. Myotonic discharges were identified by electromyography. Percussion dimpling and the typical myotonic discharges persisted after neuromuscular blockade. Distinctive histologic muscle changes included ring fibers, sarcoplasmic mass formation, variation in fiber diameter size, and internally positioned nuclei.
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Affiliation(s)
- S M Reed
- Department of Veterinary Clinical Medicine, College of Veterinary Medicine, Washington State University, Pullman
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Simpson ST, Braund KG. Myotonic dystrophy-like disease in a dog. J Am Vet Med Assoc 1985; 186:495-8. [PMID: 3972711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A mature female Rhodesian Ridgeback was determined to have a progressive, degenerative myopathy associated with myotonia, dysphagia, and marked muscle wasting. Clinical findings revealed a diffuse muscular disease with percussion dimpling, dysphagia, and creatine kinase elevation. A paroxysmal atrial tachycardia was found. Electromyography revealed a diffuse myopathy with high-frequency bizarre waves, myotonic discharges especially in the masticatory, laryngeal, and pharyngeal muscles. A few positive sharp waves were found in some of the appendicular muscles. Histopathologic and histochemical stains on skeletal muscle biopsy specimens demonstrated moderate fiber-size variation, myofiber architectural changes, muscle-fiber splitting, focal necrosis and phagocytosis, high percentage of internal nuclei, and atrophy of type-2 muscle fibers. A review of myotonic myopathies in the dog is presented. The clinical, electrophysiologic, and histochemical findings are similar to those for myotonic muscular dystrophy in man.
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Abstract
Isoforms of myosin were examined in hindleg muscles isolated from normal and myotonic goats. The muscles studied were the soleus, gastrocnemius, gluteus accessorius, semitendinosus, semimembranosus, and adductor. The isomyosins were analyzed by pyrophosphate polyacrylamide gel electrophoresis. The relative proportions of slow and fast myosin isoforms present were determined by densitometric scanning of Coomassie Blue-stained gels. All muscles contained three fast myosin isoforms and either one or two slow myosin isoforms. In normal goat, the soleus and gastrocnemius, containing 70%-75% slow isomyosins, were representative of slow muscle. The semimembranosus, the semitendinosus, and the adductor, with more than 50% fast myosin, represented a predominantly fast muscle group. The gluteus accessorius, with approximately 45% fast myosin isoforms, was intermediate between the other two groups. In the myotonic goat, a consistent and significant increase in the proportion of fast isomyosins was observed for all the muscles studied. The largest change occurred in the gastrocnemius where the incremental increase in the percentage of fast isomyosins was over 30%. All the other muscles examined had incremental increases in fast isomyosin content which ranged from 16.1% to 22.0%. These results suggest that the abnormal action potential pattern of myotonia leads to a redistribution of the myosin isoforms.
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Abstract
The pathology of two cases of canine myopathy associated with myotonia are presented. The changes were interpreted as dystrophic. The most obvious features were a rounding on cross section and variation in fibre size with numerous internal nuclei, many of which formed chains. Degeneration and regeneration were seen and there was a slight increase in perimysial and endomysial connective tissue. Only one ringed fibre was seen, but no sarcoplasmic masses. Enzyme histochemistry failed to demonstrate any selective Type I fibre atrophy. The peripheral and central nervous systems were normal in both cases.
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Durack DT, Gubbay SS, Kakulas BA. Electrophysiological studies in the Rottnest quokka with nutritional myopathy. Aust J Exp Biol Med Sci 1969; 47:581-8. [PMID: 5373689 DOI: 10.1038/icb.1969.152] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Bryant SH, Lipicky RJ, Herzog WH. Variability of myotonic signs in myotonic goats. Am J Vet Res 1968; 29:2371-81. [PMID: 5749119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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