Physiology and clinical presentation of muscle disease Flashcards
why is the sarcoplasmic reticulum important for muscle contractions
stores Ca to aid sarcomere contraction
where is Ca used in muscle contraction
Ca causes release of acetylcholine at terminal axon
released from sarcoplasmic reticulum and binds to troponin to cause it to release actin
when is the phosphagen system used to produce energy form muscle contraction
high intensity short duration exercise
List 5 substrates that the muscle can metabolise to produce energy
phosphagen system
glycogen
fatty acids
branch amino-acids
lactate
when do muscles tend to use fatty acids to produce energy
during sustained exercise
what muscle fibres are used in aerobic exercise
type 1 fibres
what muscle fibres are used during anaerobic exercise
type 2 a fibres - is moderately fast
type 2 x fibres- is fast
List 4 ways that there can be difference in muscles
between individual muscles
differences within muscle- surface vs deep
differences in breeds
training
How have horses adapted to have a higher muscular oxidative capacity
higher mitochondrial mass
higher aerobic enzymatic pool
List 3 mechanisms that counteract oxidative stress
vitamin E - sarcolemma repair
cysteine - resp chain, ROS
Q10
when does CK increase in muscle damage
CK peaks 6hr post exercise - will decrease after this point
Name 2 plasma markers of muscle damage in horses
CK and AST
when does AST increase in muscle damage
AST peaks at 24 hours- tells you what has happened but not when
takes 2 weeks to decrease
which plasma marker is better at identifiying long term muscle damage
AST
Describe how to treat muscle damage
control pain
avoid damaging effects of myoglobin release
support muscle cell recovery
