BIOL 2420 Lecture 10: Lecture 10

• School: University of Manitoba
• Department: Biological Sciences
• Course: BIOL 2420
• Professor: W.G.Anderson

Document Summary

Note: the immediate baroreceptor re ex only brings map back towards normal; lost volume must be replaced by shift in uid balance. In uences venous pressure, venous return, edv, sv & co. Regulated by hormones secreted by heart and kidney. Atrial natriuretic peptide, vasopressin (adh) and renin (begins conversion of angiotensinogen to angiotensin ii) Potent vasodilator synthesized by atrial myocardial cells; secreted in response to excess stretch of heart and inhibits: Together these responses increase urine output and decrease map. Slow changes in map are accompanied by a resetting of the baroreceptor response - pushing away from homeostasis. Still opposed minute to minute changes in pressure, but at a higher (or lower) level. No clear cut cause, but associate with obesity, high cholesterol, smoking and genetics (ex. Initially leads to ventricular hypertrophy, however, myocardial contractile function diminishes over time. Heart has a lot more work to do. Also increases risk of atherosclerosis, heart attack, kidney damage and stroke.