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+--- Thread: 12 12 12 12 12 - guest1 (/showthread.php?tid=305818)
12 12 12 12 12 - guest1 - ArchivalUser - 05-27-2008
An increase in sodium conductance is associated with
a. The plateau phase of the ventricular muscle action potential
b. The downstroke of the skeletal muscle action potential
c. The upstroke of the smooth muscle action potential
d. The refractory period of the nerve cell action potential
e. The end-plate potential of the skeletal muscle fiber
0 - ArchivalUser - 05-27-2008
ddd
0 - ArchivalUser - 05-27-2008
EEEEEEE
The channel opened by ACh
when it binds to receptors on the end plates of skeletal muscle fibers is
equally permeable to potassium and sodium. The increase in sodium permeability
allows sodium to flow into the cell and produces the end-plate
potential. The plateau phase of ventricular muscle action potentials and the
upstroke of smooth muscle action potentials are produced by an increase
in calcium conductance. An increase in potassium conductance is responsible
for the downstroke of the action potential. The refractory period is
caused by an increase in potassium conductance and a decrease in the
number of sodium channels available to produce an action potential (i.e.,
sodium channel inactivation).
0 - ArchivalUser - 05-27-2008
thanx for joining me guys....this is it for tonight... it's really late...need to sleep...hopefully, we'll post more tomorrow of cardio and respi physiology. GL all.
0 - ArchivalUser - 05-27-2008
thanks for the great ques..GN.
0 - ArchivalUser - 05-27-2008
urw... GN manik. thanx for participating.
0 - ArchivalUser - 05-27-2008
guest1 thanks for the questions, this very good review.kepp up the good work
0 - ArchivalUser - 05-27-2008
thanks... finally someone mature enough to stay on tract... i guess thats karma for those who only had bad intentions when joining this forum...