Question | Answer |
cardiac action potential | *sodium enters/depolarization to threshhold
*thershold opens vgate sodium, more sodium enters
*Sodium gates close, K channels open
*PLATEAU |
plateau is due to influx of Ca which is + ion, which flows in from ECF to ICF to this effect | maintains/extends AP time by keeping cell at +20mV |
repolarization of cardiac muscle occurs due to | due to closure of Ca channels and K outflow when additional Vgate K channels open |
smooth muscle also uses Ca from ECF to effect | *digestive/urinary processes to expel |
Ca blocking drugs used for | anti-HTN: block Ca channels in sm musc of blood vessels --> unable to constrict, therefore vasodilation remains |
Beta Blockers will | decrease bp bwo decreased CO |
heart can switch to anaerobic metabolism by this rxn | ADP + creatine kinase --> ATP + creatine |
lab test for creatine kinase tells us what | if myocardial muscles have died, as evidenced by creatine generated by anaerobic metab prior to death (thereby liberating the enzyme to blood) |
CK isoenzymes include | sk muscle (CKmm), heart (CK MB), brain (CKbb) |
cardiac muscle is loaded with these ATP producing cells | mitochondria |
*Troponin is released from myocardium @ death
*CK released @ myocardium death | heart muscle dies and these markers are present |