BIOL 2P93 Lecture Notes - Cytosol, Cyclic Adenosine Monophosphate, Oxidative Phosphorylation
Document Summary
Outline of lecture 37 (05-21 a; marban and o"rourke) Heart molecules to cells: differences between cardiac and skeletal muscle. Three factors affect contractile force: intracellular calcium: higher [ca]in gives higher force, contractile protein response to intracellular calcium: e. g. regulation by phosphorylation, loading: higher preload gives higher afterload force. Force vs. [ca]in is a steep sigmoid. Camp-dependent phosphorylation of troponin regulates its ca responsiveness: autonomic regulation. Symp stimulation b -adrengic cascade camp camp-dependent protein kinase phosphorylate : l-type ca channels: increase ca influx, ionotropic, phospholamban: accelerate ca uptake into sr, chronotropic, troponin: inhibit myofilaments and accelerate relaxation, chronotropic. Frank-starling effect: that sarcomere length changes ca sensitivity (loading effect) Cannot be explained by differences in myosin/actin overlap. Troponin c itself may be the molecular transducer between length and ca sensitivity. Outline of lecture 38 (05-21 b; marban and o"rourke) Be able to interpret the cardiac cycle on a wiggers diagram (p. 1)