KIN 272 Lecture Notes - Lecture 7: Tachycardia, Atrioventricular Node, Cardiac Output
Document Summary
Parasympathetic innervation at sa node and av node. Locations of pacemaker cells at av and sa node. Slows the rate of depolarization and slows heart rate. Innervation in cardiac muscle increases force and pressure. Exercise (by increased sympathetic activity, increased skeletal muscle and respiratory pumps) Increased ventricular filling time (due to decreased heart rate) Cns output (in response to exercise, fright, anxiety, or decreased. More blood returns to heart = heart contracts more to push it out. Beta 1 receptors are adrenergic receptors in heart. Cause increase at ca2+ release and increase depolarization in pacemaker cells. Flow: match blood flow to metabolic activity. Tissue can be so thick it needs its own blood supply. Farther from heart blood goes from arteries to veins. Stores energy/pressure from heart so there"s enough energy and continued blood flow when the heart relaxes. Valves prevent backflow of blood not enough pressure in system to keep blood from backflow.
