Question

Describe the role of the autonomic nervous system in controlling heart rate (include neurotransmitters, whether it increases and/or decreases heart rate and what specific part of the brain exerts the most control over heart rate). Include neurotransmitters and receptors.

Answer 1

Ans:- Part of brain which control heart rate is MEDULLA OBLONGATA.

Medulla – The primary role of the medulla is regulating our involuntary life sustaining functions such as breathing, swallowing and heart rate. As part of the brain stem, it also helps transfer neural messages to and from the brain and spinal cord. It is located at the junction of the spinal cord and brain.

How ANS effect heart rate:-

ANS have two component

Sympathetic nervous system and parasympathetic nervous system

Sympathetic nervous system release nor epinephrine and epinephrine. They bind to B2 receptor of heart to increase heart rate.

Parasympathetic nervous system mainly act via vagus nerve it release acetylcholine which act on M2 receptor to open K + channel and also decreases level of cAMP hence decrease heart rate.