Classic Classic Quiz Cardiology : Calcium Removal by Tommymoran Tommymoran 3 played - 10 yrs ago Prep for midterm QUIZ 11 QUESTIONS expert 1 Which of the following is responsible for the majority of calcium clearance from the cytoplasm of ventricular myocytes? Sarcolemma Ca ATPaseNa /Ca exchangerSarcoplasmic Endoplasmic Reticulum Ca ATPaseThey're equally responsible 2 What is the primary function of the Ca uniporter in mitochondria in ventricular myocytes? Reduce intracellular Ca to allow muscle relaxationIncrease ATP production via glycoylsis to sustain energy expenditure of active ion-pumpsFacilitate diffusion of oxygen molecules across the mitochondrial membraneB and C 3 2 Cytoplasmic Ca ions cooperatively bind to the Sarcolemmal Ca ATPase to expose what residue for ATP binding? GlutamateGlutamic AcidAspartateAspartatic Acid 4 Sarcolemmal Ca ATPase may interact with NOSynthases in caveolae to... Reduce local Ca levels, reducing NOS synthesis, limiting inotropy and cell contractilityReduce local Ca levels, increasing NOS synthesis, increasing inotropy and cell contractilityReduce local Ca levels, increasing NOS synthesis, limiting inotropy and cell contractilityReduce local Ca levels, reducing NOS synthesis, increasing inotropy and cell contractility 5 Under what circumstance(s) will the NCX exchange 4Na+ for a Ca instead 3Na ? Extracellular AlkalosisExtracellular AcidosisExchanger is in Rod CellsB and C 6 At Em below -50mV, the NCX will pump Na out of the sarcolemma and Ca in. What "mode" is the exchanger said to be in? ForwardReverseRightLeft 7 In heart failure, SERCA levels are typically... IncreasedDecreasedConstantIrrelevant 8 One treatment for heart failure with reduced levels of SERCA is to... Transfect SERCA2a genes via adenovirus into myocardiumTreat heart with digoxin. Increased calcium levels will signal SERCA transcription.Percutaneously inject SERCA formulation into myocardiumA and B 9 What is the result of Phospholamban's interaction with SERCA? Increased rate of Ca sparksIncreased Ca efflux from SRReduced uptake of cytosolic Ca into SRA and C 10 How does mutant PLB interfere with the regulation of wild-type PLB? It will irreversibly bind and inactivate PKA, thus preventing the phosphorylating and inhibition of wild-type PLBIt will bind to RyR, and reduce intracellular Ca levelsIt has no effect on wild-type PLB regulationA and B 11 How does phospholamdan contribute to CPVT? PKA phosphorylates SERCA, which will activate phospholamdan to bind RyRPKA will phosphorylate it, dissociating it from SERCA and overloading the SR.Phospholamdan is fat and uselessA and B and C A mistake in this Quiz ? Contact the author Commentaires
