Exam 2 - Wendt (Arrhythmia/CHF) Flashcards
(109 cards)
_______ cells have automaticity
Pacemaker
pacemaker cells have (what ion) dependent spikes
Ca2+
Ventricular myocytes have (what ion) dependent spikes
Na+
Pacemaker Cells or Ventricular Cells?
have a very fast/immediate/vertical depolarization
Ventricular cells
Pacemaker Cells or Ventricular Cells?
have Ca2+ dependent spikes
Pacemaker
Pacemaker Cells or Ventricular Cells?
have Na+ dependent spikes
Ventricular
Pacemaker Cells or Ventricular Cells?
Have high automaticity
pacemakers
Pacemaker Cells or Ventricular Cells?
have low automaticity
ventricular
Pacemaker Cells or Ventricular Cells?
are specialized non-contractile cells
Pacemaker
Pacemaker Cells or Ventricular Cells?
are contractile cells
ventricular
what are the phases of a Pacemaker cells action potential?
In order: Phase 4,0,3,4
what is phase 4 in pacemaker cell action potential
“funny” current makes diastolic pacemaker current
annnnd
K+ channels/current is activated by vagus
what is phase 0 in pacemaker cell action potential
calcium channel carries AP upstroke
what is phase 3 in pacemaker cell action potential
repolarizing K+ current
Myocyte action potential phases? (in order)
IN ORDER: Phases 4,0,1,2,3,4
what is phase 0 in myocyte cells action potential
Na+ channel carries AP upstroke
what is phase 1 in myocyte cells action potential
repolarizing K+ current (“transient upward”???)
what is phase 2 in myocyte cells action potential
plateau Ca2+ current critical for muscle contraction
what is phase 3 in myocyte cells action potential
repolarizing K+ current
what is phase 4 in myocyte cells action potential
pacemaker current (very minimal?)
Acetylcholine decrease _____ and ____ currents
HCN; Ca2+
ACH activates ______ which causes hyperpolarization
GIRK
_____ activates GIRK which causes hyperpolarizaiton
ACH
ACH stimulates the G_____ channel
G (alpha I)