What Is The Role Of Sympathetic Nervous System In Cardiac Function?
I would explain as follows:
Detailed Answer:
Hello!
Welcome back on HCM!
I am a cardiologist working in the ICU of a Universitary Hospital Center.
I deal with acute cardiac patients everyday and have wide knowledge on the heart normal physiology and cardiac disorders.
I would explain that the sympathetic nervous system plays an important role in regulating the heart function.
The chatecholamines (adrenaline and noradrenaline) which are the main mediators of the sympathetic nervous system are released by the medullary portion of the adrenal glands.
They lead to an increase in the heart rate and contractility, leading to an increased cardiac output (blood flow pumped from the heart into the aorta and than to the other arteries).
From the other hand they are responsible for vessel constriction, leading to higher blood resistance and an elevated blood pressure.
Sympathetic nervous system can be activated by different stimuli : psychological and physical stress, an alarm (like low blood pressure or an incoming danger to the human body, etc.).
Hope to have clarified some of your uncertainties.
If you have any other questions, please do not hesitate to ask me!
Best wishes,
Dr. Iliri