Carotid baroreceptors:: (A) Are important in the rapid, short term regulation of arterial blood pressure, (B) Do not fire until a pressure of approximately 100 mm Hg is reached, (C) Adapt over 1 to 2 weeks to the prevailing mean arterial pressure, (D) Stretch reflexively decreases cerebral blood flow
Answer is A. Ans. A. Are important in the rapid, short term regulation of arterial blood pressureThe function of these baroreceptors is the rapid short-term regulation of arterial blood pressure. The receptors start firing at a pressure of approximately 40 mm Hg. They completely adapt over 1 to 2 days, not weeks. In general, changes in baroreceptor activity have little effect on cerebral blood flow. The sympathetic activity following a fall in blood pressure results in increased heart rate and contractility, which raises myocardial metabolism and coronary blood flow,