Muscle Flashcards
Epimyusium
covers entire muscle
perimysium
covers muscle fasicle
endomysium
covers each muscle cell
A bands
I bands
a bands dark
i bands light
actin vs myosin
thin -actin part of the I band
thick myosin part of the a band
titin
associated with myosin
during relaxation titin generates passive tension
Desmin
intermediate filament
encircles z disk of each sarcomere
attaches to costameres (special sarcolemma)
Muscle contraction what shortens what stays the same
The H and I band reduce
A and Z stay the same
What is the back up source of energy during muscle contraction?
hydrolysis of creatine phosphate
what would an antibody against the voltage gated K channel
lasting depolarzation state following release of neurotransmitter
Antibody to voltage gated CA 21 channel
continous inflow of Ca causing muscular weakness
Botulinum toxin
prevents release of acetylcholine
binds to presynaptic memebrane
Curare
binds to acetylcholine receptor
prevents binding of acetylcholine
paralysis
Myasthenia gravis
autoantibody binding to the acetylcholine receptor causes myasthenia gravis (fatigue with exercise)
Muscle Contraction
- action potential along sarcolemma reaches t tubule
- depolarization
- l type voltage sensitive calcium channel (membrane transverse tubule) changes conformation
- conformationc hange induces ryanodine sensitive calcium channel in membrane of sarplasmic reticulum release calcium
- ryanodine sensitive ca channel opens and release calcium
calsequestrin
binds calcium in the lumen of sarcoplamic reticulum
ca-atpase
mediates return of calicum to the sarcoplasmic lumen
Satellite cells
stem cell population
for stres or trauma
What is in the longitudinal component of the intercalated disk
gap juntion
what is in the transverse component of the intercalated disk
desmosomes and fascia adherentes
phospholamban
controls active transport of calcium into the lumen of the sarcoplasmic reticulum
Where are triads seen?
skeletal muscle
where are diads seen?
cardiac muscle
at what levels are diads found?
at the level of the z disc
at what levels are triads found?
at the level of the a/ I junction
Cardiac muscles have what type of nuclues
central located
Mycardial ischeemia
occlusion of the coronary artery results within the first 24 hours
pyknotic (irregulary shaped nucleus)
caveolae
depressions of plasma memebrane
fluid and electrolyte transport (pinocytosis)
red muscle fibers versus white
red-jogging mitocondria
white-sprinting
