Muscle and Tendon Flashcards
The capillary network that supports the myofiber is carried in the :
endomysium
A muscle fascicle, or bundle, is surrounded by the :
perimysium
Resting cells that lie between the basal lamina and the sarcolemma are:
satellite cells
The Z band contains contractile/noncontractile elements.
non-contractile
Besnoitia darlingi is a common apicomplexan of what species?
opossum, infects fibroblasts and endothelial cells (Opossums are about the least darling things on earth)
Type I muscle fibers are red/white, oxidative/glycolytic and fast/slow.
red, slow and oxidative. (On day 1 of exercise you are SOR (slow, oxidative, red)).
Laryngeal hemiplagia results from denervation atrophy after axonal degeneration of the ________?
left recurrent laryngeal nerve
Muscle atrophy due to cachexia is mediated through?
TNF (AKA cachectin)
Primary myopathies affect which type of muscle fiber?
Type I (1=primary)
Denervation atrophy affects what type of muscle fiber?
both Type I and Type II (no nerve = no muscles regardless of type)
Disuse and cachexia atrophy of muscles primarily affects what types of muscle fibers?
Type II (On day 2 of exercise, you don’t want to use your muscles anymore = disuse)
Double muscling is the result of the absence of what regulatory muscle protein?
myostatin. Lack of myostatin allows for unregulated hypertrophy of muscle
What is the most sensitive and specific indicator of skeletal muscle injury? A. Myoglobin B. Troponin T C. Serum Creatine kinase D. Serum AST
Serum CK is the most sensitive and specific. Myoglobin and AST are also used clinically, but CK is the most specific. Troponin T is specific for myocardial injury.
Muscle necrosis is mediated by the influx of what into the cytosol from the ECF? A. Sodium B. Potassium C. Calcium D. Hydrogen ions
Calcium causes irreversible damage as a result of initiation of Ca-dependent processes in the cytosol and overload of Ca within the mitochondria leading to energy failure, membrane damage and necrosis.
Polysaccharide storage myopathy in Quarterhorses is the result of a defect in which gene? A. GBE1 B. GYS1 C. Dystrophin D. HYPP
Glycogen synthase 1 (GYS1) is the defective gene in polysaccharide storage myopathy. GBE1 is for glycogen branching defect in horses, Dystrophin is for X-linked muscular dystrophy, and HYPP is for hyperkalemic periodic paralysis in the Impressive line of horses.
What breeds of dogs are affected by phosphofructokinase deficiency?
SPANIELS!! English springer and American Cocker
Myophosphorlyase deficiency affects what breed of cattle?
Charolais
Exercise-induced collapse affects Labrador Retrievers with a defective gene ________?
Dynamin 1
Myostatin is associated with what clinical presentation
double muscling in beef cattle and whippets
Porcine stress syndrome leading to PSE meat is associated with a defective gene ______?
Ryanodine receptor
Malignant hyperthermia in Quarter horses and dogs is associated with what defective gene?
ryanodine receptor 1
The histologic finding of pigs with splayleg is:
myofibrillar hypoplasia: reduction in muscle fiber diameter and an abnormally small mass of myofibrils within muscle fibers. Also stains very lightly with eosin. but PAS shows accumulation of cytoplasmic glycogen.
Double muscling affects the:
A. size of the myofiber
B. structure of the myofiber
C. number of fibers
the number of muscle fibers
The breed of dog best known for X-linked muscular dystrophy is:
Golden Retriever