The autonomic nerve pathways connect different organs to the brain stem or spinal cord. There are also two key neurotransmitters, or chemical messengers, that are important for communication within the autonomic nervous system. Acetylcholine is often used in the parasympathetic system to have an inhibiting effect while norepinephrine often works within the sympathetic system to have a stimulating effect on the body.

Norepinephrine - A hormone that is released by the adrenal medulla, by the sympathetic nerves function, and as a neurotransmitter. It is also used as a drug to raise blood pressure.
Acetylcholine - A compound that occurs throughout the nervous system that functions as a neurotransmitter.
Adrenal Medulla - Part of the adrenal gland. It is located at the center of the gland it is surrounded by the adrenal cortex.
Neurotransmitter - A chemical substance that is released at the end of a nerve fiber by the arrival of a nerve impulse by diffusing across the synapse or junction. This causes the transfer of the impulse to another nerve fiber, a muscle fiber, or some other structure.
Adrenal Gland - Either of two small endocrine glands, one located above each kidney. The outer portion, or cortex, secretes steroid hormones (corticosteroids). The inner portion, or medulla, secretes epinephrine and norepinephrine.
Adrenal Cortex - produces steroid hormones which regulate carbohydrate and fat metabolism and mineralocorticoid hormones which regulate salt and water balance in the body.

	Created by Bdy Ecology about 10 years ago

Note on The Human Body Lesson 2.0, created by Bdy Ecology on 26/02/2016.

The Human Body Lesson 2.0