AUTOREGULATION-BARORECEPTORS

SUMMARY

1. Baroreceptors are stretch receptors in the walls of the heart & blood vessels. 2. Increased baroreceptor discharge inhibits tonic discharge of sympathetic nerves & excites vagal innervation of the heart.
3. This causes vasodilation, venodilation, hypotension & bradycardia ⟹ decreasing cardiac output.
4. In chronic hypertension, the baroreceptor reflex mechanism is ‘reset’ to maintain an elevated rather than a normal BP.

DIFFERENT RECEPTORS
5. Carotid sinus & aortic baroreceptors monitor arterial circulation.
6. Receptors in the right atrium monitor venous return.
7. Receptors in the left atrium monitor pulmonary circulation.

Reference(s)

Barrett, K.E., Barman, S.M., Boitano, S., Brooks, H.L., Weitz, M., Brian Patrick Kearns, Ganong, W.F. and Mcgraw-Hill Education (Firm (2016). Ganong’s review of medical physiology. 25th ed. New York: Mcgraw Hill Education.
Hall, J.E. and Hall, M.E. (2020). Guyton And Hall Textbook Of Medical Physiology. 14th ed. S.L.: Elsevier - Health Science.
West, J.B. and Luks, A.M. (2021). West’s Pulmonary Pathophysiology. Lippincott Williams & Wilkins.