Biochemistry Flashcards
what is the ion responsible for phase 0 (upstroke) of SAN AP?
Calcium
what is ion responsible for phase 4 (gradual incline/If) of SAN AP?
Na
in calcium-indiced-calcium release, what is role of cAMP?
phosphorylates ryanodine receptor allowing calcium to exit SR into cell and phosphorylates SERCA-PLB receptor to allow Ca to return into SR
does angiotensin II induce myocardial contraction?
no
what are adrenergic receptors all coupled to?
G-proteins
what does alpha 1 receptor do?
vasoconstriction
alpha 2 receptor
vasodilation (inhibition of axonal NE release)
Beta 1 receptor
myocardial contraction and chronotropy
Beta 2 receptor
vasorelaxation
what receptor does clonidine bind to?
alpha 2 (presynaptic NE)
which receptors does epinephrine hit?
a1, B1 ,B2
which receptors does Norepi hit?
a1, B1
which receptors does dobutamine hit?
B1, B2
which receptors does phenylephrine hit?
a1
which receptors does phentolamine hit?
a2
which receptors does propranolol hit?
B1, B2
name 3 receptors that are in vasculature.
alpha 1, 2, B2
name 1 receptor in myocardium (biochem lecture)
B1
what is ligand for parasympathetic receptors?
acetylcholine
what does acetylcholine do to a vessel if there is intact endothelium? what about denuded endothelium?
increase NO–> vasodilation
can’t inc NO–> vascononstriction
which of the following is a direct thrombin inhibitor: rivaroxaban, dabigatran?
dabigatran
when there is tissue injury, is it the intrinsic or extrinsic clotting pathway that first gets activated?
extrinsic
name the enzyme inhibited by fondaparniux, rivaroxaban, apixaban
Xa
what is inheritance pattern of Becker’s CM?
X-linked
what is inheritance pattern of Marfan’s?
Autosomal Dominant
which gene and what chrome. is responsible for Marfan’s?
fibrillin , chrom 15
is Ao usually involved in Ehler’s Danlos?
no
what chess wall deformity is associated with marfans?
pectus excavatum
what is main inheritance pattern for long QT syndrome?
AD
what is main inheritance pattern for Brugada syndrome?
AD
is brugada syndrome a gain or loss of fxn and what gene is involved?
loss of fxn
SCN5A
inheritance pattern of familial hypercholesterolemia?
AD
which disease has an autosomal dominant inheritance pattern with variable penetrance and sarcomeric mutation?
HCM
what is the most frequent mutation in HCM?
myosin binding Protein C
what is the myocardium’s preferred source of energy?
FA’s
do BB’s prevent poor calcium flux intracellularly?
yes
in CHF, is there emote calcium in the cytosol or SR?
cytosol
