Cardiac Performance, Dr. D. Penney


Control of Cardiac Performance: HEART RATE

Extrinsic control:

Release of the following substances from the sympathetic and parasympathetic branches of the autonomic nervous system, effect chronotropicity:

acetylcholine (-) - neural release
norepinephrine (+) - neural release
epinephrine (+) - blood borne

These actions are mediated through cardiopulmonary receptors, such as the carotid sinus (aortic) baroreceptors, carotid (aortic) body chemoreceptors,
central chemoreceptors, venae cavae/atrial volume receptors (Bainbridge Reflex), and the ventricular volume receptors.


Intrinsic control:

Environment - ischemia, stretch, K+, Ca++, temperature



Last changed 02/17/03


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