PSL201Y1 Lecture Notes - Lecture 19: Central Venous Pressure, Parasympathetic Nervous System, Stroke Volume
Document Summary
Cardiac output regulation regulate heart rate and stroke volume extrinsic and intrinsic regulation: extrinsic-neural and hormonal intrinsic: autoregulation. Stimulation of sympathetic nerve, sympathetic cardiac nerve leads to increased heart rate. Slope reaches threshold faster due to opening of funny and ca+2 channels allowing faster depolarization of membrane since sympathetic nerve projects the sa node where pacemakers sitting at. Autonomic inputs to heart there are projections from sympathetic cardiac nerve to sa node (control heart rate) sympathetic nerve not only to sa node but to av node as well, sympathetic nerve also innervates ventricular myocardium (heart muscle) Parasympathetic(vagus) nerve projects to sa and av node only, does affecting heart rate. Stimulation of parasympathetic nerve will decrease heart rate, exactly opposite effect of sympathetic nerve. Sympathetic and parasympathetic nerve projections is sympathetic projects to sa and av node and also projects to ventricular myocardium whereas parasympathetic only innervates sa and. Heart rate is determined by sa node firing rate.
