Autonomic nervous system anatomy

2021-02-12 12:00 AM

The autonomic nervous system is divided into two parts, the sympathetic and the parasympathetic part, operating on the opposite principle, the autonomic nervous system has structure.

General perception

The autonomic nervous system is also known as the vegetative nervous system, which consists of nerve fibres that go from the central nervous system to the smooth muscles (glands, organs, blood vessels) and heart muscle.

The autonomic nervous system is divided into two parts, the sympathetic part and the sympathetic part, operating on the opposite principle. The autonomic nervous system is made up of:

Autonomic nerve centre: includes the nuclei in the brain or spinal cord.

Nerve fibres from the central nucleus to the periphery include two types: pre-ganglion fibres (from the nucleus to the nodes) and post-ganglion fibres (from the ganglia to the organs).

There are 3 types of autonomic nerve nodes:

Parenchymal nodes are located along both sides of the spine.

The anterior lymph nodes live or the anterior lymph nodes.

The terminal is right near the organs.

Autonomic plexuses are interlocking networks of parasympathetic and parasympathetic nerve fibres before entering an organ.

The sympathetic system

Central part

The lateral medial nucleus in the medullary segment from chest 1 to lumbar 3 (T1 - L3).

Peripheral part

The anterior ganglion fibre follows the living spiny nerve into the white pine branch to the parietal parasympathetic ganglia or through these nodes to the living anterior lymph nodes.

Parenchymal lymph nodes: There are two parasympathetic ganglia on either side of the spine from the base of the skull to the sacrum. Each chain has 23 nodes, connected by branches of the amygdala, forming a sympathetic body and consists of the following parts:

There are the upper neck, middle and lower neck lymph nodes in the neck; Lower cervical lymph nodes often combine with chest 1 to form stellar lymph nodes.

In the thoracic, lumbar and same region: 11 to 12 thoracic lymph nodes, 3 to 4 lumbar lymph nodes, 4 to 5 same lymph nodes.

In the idiopathic region, the two sympathetic bodies approach each other and merge into a tail node.

Live anterior lymph nodes: have visceral lymph nodes, mesenteric lymph nodes, lower mesenteric lymph nodes, renal master nodes and diaphragm.

Post-ganglion fibres: from paranasal or anterior lymph nodes, sympathetic nerve fibres pass through the grey pine branch, then into the spinal cord to reach the organ they dominate.

Sympathetic system


Consists of two parts:

In the brain is the nucleus of cranial nerves: III, VII, IX, X.

In the spiny medulla is the medial-lateral medial column 2 to 4 (S2-4).


Pre-ganglion fibre: depending on different origins.

From the central part of the brain: according to the cranial nerves III, VII, IX, X to the terminal lymph nodes (lymph nodes, lymph nodes of the female palate, lymph nodes below the jaw).

From the central spinal cord: follow the anterior roots of the spinal nerves to the terminal nodes in the pelvic region.

End nodes: located near or within the walls of the organs they dominate.

Post-ganglion fibre: very short, from the terminal ganglia entering the organ.

The function of the autonomic nervous system

The sympathetic and sympathetic systems have an almost opposing effect. For example, the sympathetic system relaxes the pupils while the sympathetic system contracts the pupils. However, they are all under the command of the cerebral cortex and work together.

Effects of the autonomic nervous system





Dilated pupils



Little or no effect on the \secretion

Stimulate secretion

Salivary glands

Reduce secretion

Increased secretion





Increased rhythm, increased contractility

Reduce the rhythm

Stomach, intestines (peristalsis

and secretions)



Sphincter of the stomach and intestines




Condensation of the vas deferens, seminal vesicles, prostate and uterine muscles, vasoconstriction



Little or no effect

Constraint into the bladder

Adrenal medulla

Stimulate secretion

Little or no effect

Blood vessels in the trunk and limbs



Figure. Autonomic nervous system diagram

  1. Nerve IX 2. Nerve X 3. Organ lymph node 4. Pelvic parasympathetic fiber 5. Parenchymal nodule