NURS 245 Lecture Notes - Lecture 20: Distal Convoluted Tubule, Vascular Resistance, Baroreflex
Document Summary
Control of systemic blood pressure: see chart map = hr x sv x tpr-(hr and sv at the heart itself-how much and how hard the heart is pumping. Life style a) chronic stress-you have cortisone release and then cortisone potentiates any epinephrine around and causes vasoconstriction b) cigarette smoking-causes vasoconstriction. Age-lose elastin in blood vessels so they don"t stretch as much. Long term cortisone-cortisone itself potentiates epinephrine and also causes salt and water retention. Positive feedback with fibrosis-if you constrict it can lead to atherosclerosis which leads to more constriction. Increased workload on heart-causes cardiac hypertrophy and leads to heart failure. Peripheral ischemia-due to cardiac hypertrophy the cells need more oxygen depriving the peripheral tissue. You also have a decreased blood flow to the capillaries due to an increase in tpr of the arterioles. Retinopathies-tpr is increased causing less blood flow to get to the kidneys.
