PATHOLOGY

Detailed explanation-1: -The sympathetic nervous system (SNS) releases the hormones (catecholamines-epinephrine and norepinephrine) to accelerate the heart rate. The parasympathetic nervous system (PNS) releases the hormone acetylcholine to slow the heart rate.

Detailed explanation-2: -Your sympathetic nervous system is best known for its role in responding to dangerous or stressful situations. In these situations, your sympathetic nervous system activates to speed up your heart rate, deliver more blood to areas of your body that need more oxygen or other responses to help your get out of danger.

Detailed explanation-3: -Sympathetic nerve accelerates heart beat due to adrenaline. Adrenaline or epinephrine is a hormone secreted by the medulla of the adrenal gland. It prepares the body for emergency action. It increases strength and rate of heart beat.