NM Disease

Question 1

Myosin ATPase pH 9.8

Answer 1

Type 1 fibers (slow twitch) light staining

Type 2 fibers (fast twitch) dark staining

Question 2

Myosin ATPase incubation at pH 4.3

Answer 2

Type 1 fibers dark staining
Type 2A and 2B fibers light staining
Type 2C fibers dark staining

Question 3

NADH dehydrogenase

Answer 3

Stains mitochondria and sarcoplasmic reticulum

Question 4

Gomori modifies trichromatic

Answer 4

Stain for nucleuoproteins and lipoproteins; nuclei and aggregates of mitochondria and SR stain brilliant red. Stain of choice for demonstrating nemaline rods and ragged red fibers. Excellent stain for evaluation of nerve fiber morphology

Question 5

Periodic acid Schiff

Answer 5

External basal lamina, glycogen and myelin. Good for detection of glycogen storage disorders

Question 6

Oil red O

Answer 6

Stains triglyceride fats; good for staining intramyofiber lipid stores and detection of lipid storage disorders

Question 7

Protein A-peroxidase

Answer 7

Detection of Ig at NMJs, ANA, anti-atrial antibodies

Question 8

Drug-induced myopathies

Answer 8

D-penicillamine, cimetidine, TMS, tapazole in cats

Question 9

Endocrine myopathies

Answer 9

Characterized by generalized atrophy of type 2 muscle fibers. A shift to type 1 fiber predominance, nemaline rods, and PAS positive deposits may be observed in hypothyroidism. Lobulated fibers may be found in chronic Cushings

Question 10

Cytochrome c oxidase deficiency

Answer 10

Ragged red fibers, excessive lipid droplets

OES

Question 11

Pyruvate dehydrogenase phosphate 1 deficiency

Answer 11

Ragged red fibers and excessive lipid droplets

Clumber, Sussex spaniels

Question 12

Disorders of lipid metabolism

Answer 12

Oil red O lipid deposits in muscle
Acquired fatty acid oxidation defect in pasture fed horses
Primary or secondary carnitine deficiency
Unclassified in wire-haired pointing griffons

Question 13

Disorders of glycogen metabolism

Answer 13

PAS positive deposits in muscle biopsy
Myophosphorylase deficiency - Charolais cattle
Phosphofructokinase deficiency- springer spaniels, cocker spaniels
Polyglucan storage (ladies) - mini wire haired dachshunds
Polysaccharide storage - quarter horse, warmblood, draft breeds

Question 14

Dystrophin deficiency

Answer 14

X-linked but affected females reported
Golden retriever, Rottweiler, GSHP, Irish terrier, Samoyed, miniature schnauzer, Brittany spaniels, rat terrier, PWC, Labrador retrievers, Japanese spitz, CKCS
Hypertrophic MD in some DSH

Question 15

Laminin a2 deficiency

Answer 15

Major component of basal lamina that surrounds each muscle fiber
One of the extra cellular ligand for the dystrophin-associated glycoprotein complex that links the extra cellular matrix and contributes to the stability of the muscle basement membrane

Question 16

Sarcoglycan deficiency

Answer 16

Part of the dystrophin glycoprotein complex which stabilizes myofiber membranes during contraction
Chihuahua, cocker spaniel, Boston terrier- epsilon subunit of sarcoglycans, Doberman

Question 17

Collagen VI deficiency

Answer 17

Multiple limb deformities in Labrador retriever at 5mo; weakness at 6wo in Landseer dogs
Dx via muscle bx

Question 18

Myotonia congenital

Answer 18

Chow chow, miniature schnauzer, staffordshire terrier, Australian cattle dog, domestic cats

MS/ACD/cats - mutations in skeletal muscle voltage-dependent chloride channel (CLCN1)

Question 19

Centronuclear myopathy in Labrador retrievers

Answer 19

PTPLA mutation

Genetic test available

Question 20

X-linked myotubular myopathy

Answer 20

Mutations in myotubularin gene (MRM1) in Labrador retrievers and Rottweiler
Identified in Manchester terriers but mutation unknown
Muscle bx still required for characterization in early onset myopathy in breeds w/o genetic test

Question 21

Centronuclear myopathy

Answer 21

Great Danes - mutation in BIN1 gene

Border collies - mutation unknown

Question 22

Nemaline rods myopathy

Answer 22

Border collie, cat, American bulldog - nebulin gene

Question 23

Myostatin deficiency

Answer 23

Whippet

Mutation identified

Question 24

Myofibrillar myopathy

Answer 24

Mixed breed dog

Question 25

Congenital myasthenia syndromes

Answer 25

COLQ gene mutation - encodes collagenous tail of AChesterase: Labrador retrievers, Devon Rex, Sphinx, Golden retrievers CHRNE gene mutation- encoding epsilon subunit of AChR in JRT CHAT gene mutation - choline acetyltransferase in old danish pointing dogs

Question 26

Spinal muscular atrophy

Answer 26

Rottweiler, Brittany spaniel, Maine coon cat, EMND Genetic test available for Maine coon cat condition

Question 27

Sensory neuropathy

Answer 27

Dachshund, pointer, border collie, greyhound, Swedish golden retrievers Mutation identified and genetic test available for BC Mutation identified in mitochondrial polyneuropathy affecting Swedish golden retriever

Question 28

Giant axonal neuropathy

Answer 28

GSD

Question 29

Progressive axonopathy

Answer 29

Boxer

Question 30

Hypertrophic neuropathy

Answer 30

Tibetan mastiff

Question 31

Globoid cell leukodystrophy

Answer 31

WHWT, cairns terrier

Question 32

Inherited polyneuropathy

Answer 32

Leonberger, St. Bernard, miniature schnauzer, Pyrenean mountain dogs, Rottweiler, Samoyed, Alaskan malamute Mutation identified in AM Multiple mutations associated with Leonberger polyneuropathy

Question 33

Hyperchylomicronemia

Answer 33

Cats

Question 34

Hyperoxaluria

Answer 34

Cats

Question 35

Chorea

Answer 35

Abrupt nonsustained contraction of different groups of muscles in the same patient

Question 36

Dystopia

Answer 36

Sustained involuntary contraction of a group of muscles

Question 37

Tetany

Answer 37

Sustained involuntary contraction of extensor muscles that is variable intermittent

Question 38

Athetosis

Answer 38

Prolonged contraction of trunk muscles causing a bending or writhing motion

Question 39

Ballism

Answer 39

Abrupt contraction of limb muscles causing a flailing movement of the limb

Question 40

Myoclonus

Answer 40

Shock like contraction of a muscle or muscles that tends to occur repeatedly in a rhythmic pattern and may persist during sleep

Question 41

Tremor

Answer 41

Involuntary rhythmic oscillating movement of fixed frequency resulting from alternate or synchronous contraction of reciprocally innervated antagonistic muscles Should cease with sleep

Question 42

Myokymia

Answer 42

Involuntary rippling of muscles that persists even during sleep and under anesthesia

Question 43

Neuromyotonia

Answer 43

Muscle stiffness and persistent contraction related to and underlying spontaneous repetitive firing of motor unit potentials

Question 44

Dyskinesia

Answer 44

Impairment of the power of voluntary movements resulting in fragmented or incomplete movements

Question 45

Synapsin 1

Answer 45

Controls the availability of synaptic vesicles

Question 46

Synaptotagmin

Answer 46

Associated with N-type Ca2+ channels

Question 47

Synaptobrevin

Answer 47

Vesicles-associates membrane protein | Essential for exocytosis

Question 48

Syntaxin and synaptosome-associated protein 25

Answer 48

Along with synaptobrevin, essential components of the exocytosis process

Question 49

N-ethylmaleimide-sensitive fusion protein (NSF)

Answer 49

Involved in neurotransmitter release

Question 50

NSF-attachment proteins

Answer 50

Involved in neurotransmitter release