CCBs Flashcards
what are the 3 chemical structures of CCBs (P,D,B)
phenylalkylamines, dihydropyridines, benzothiazepines
what are the 4 common SEs of CCBS (SH, PE, F, H)
systemic hypotension, peripheral edema, flushing, headache
what 2 CCB classes are selective for the AV node?
phenylalkylamines, benzothiazepines
which CCB class is selective for the arteriolar beds?
dihydropyridines
which CCB is a phenylalkylamine?
verapamil
which CCB is a benzothiazepine?
diltiazem
what are the 5 dihydropyridines? (F,A,N,N,N)
felodipine, amlodipine, nicardipine, nimodipine, nifedipine
Non-dihydropyridines work at what 2 areas of the heart that the dihydropyridines don’t?
SA node, AV node
what is a first generation dihydropyridine?
nifedipine
what is a second generation dihydropyridine?
nicardipine
what is a third generation dihydropyridine?
amlodipine
what CCB has the greatest coronary artery dilation?
nicardipine
does verapamil or diltiazem depress the SA and AV nodes more?
verapamil
what are the three types of calcium channels?
L, N, T
what calcium channels do vascular and cardiac SM contain?
L-type, T-type
what calcium channel do nerves contain?
N-type
what are the 5 subunits on the L type Ca channel?
alpha1, alpha2, beta, gamma, delta
what L-type channel subunit provides the central part of the channel and the main path for Ca entry?
alpha1
all CCBs bind to what subunit to diminish entry of Ca ions into cells?
alpha 1
CCBs bind to L-type Ca channels in what 3 ares? (VSM, CM, CNT)
vascular smooth muslce, cardiac myocytes, cardiac nodal tissue
Cytoplasmic Ca concentration plays an important role in the degree of tension where? (VSM)
vascular smooth muscle
by blocking L-type Ca channels and diminishing the concentration of cytoplasmic Ca, vascular SM does what? (R)
relaxes
cardiac contractility is dependent on the influx of what into cardiac cells?
calcium
ca binds to what protein?
troponin
by binding to troponin, ca allows what 2 proteins to interact?
actin, myosin
the greater degree of actin and myosin interaction, the greater degree of what? (CC)
cardiac contraction
by decreasing myocardial force generation and contraction, what negative effect is this?
negative inotropy
what 2 phases do CCBs work on nodal AP?
phase 4 and 0
what phase do CCBs work on myocytes?
phase 2
by blocking phase 4 of nodal cells, CCBs are slowing down the nodal cells ability to get where?
thershold
what is happening in phase 4 of the nodal cells that CCBs are slowing? (SSD)
slow spontaneous depolarization
what is happening in phase 0 of the nodals cells that CCBs are slowing?
depolarization
AKA for phase 2 of myocyte cells?
plateau phase
by extending phase 2 of myocyte cells, what are CCBs prolonging?
ERP
since CCBs slow the conduction thru the AV node and decreasing the HR, so them has what negative effect?
chronotropy
CCBs decrease conduction velocity in the heart thru the AV node causing them to have what negative effect?
dromotropy