体自主流出是同情的

The parasympathetic division of the autonomic nervous system (ANS) regulates rest and digestion functions in the body. It works in opposition to the sympathetic division, promoting relaxation, conservation of energy, and digestion. The parasympathetic division consists of preganglionic fibers originating from specific cranial nerves (III, VII, IX, X) and the sacral spinal nerves (S2-S4). These fibers synapse with postganglionic neurons in the terminal ganglia, innervating various organs and...

The human nervous system is divided into two main parts: the central nervous system (CNS) and the peripheral nervous system (PNS). The CNS is composed of the brain and spinal cord, while the PNS contains nerve cells, clusters of nerve cells, and the sensory receptors that are outside the CNS. The PNS has two types of nerve cells: sensory (afferent) and motor (efferent). Sensory cells send signals to the CNS from receptors, and motor cells carry signals from the CNS to organs, muscles, and...

The cranial part of the parasympathetic division plays a crucial role in regulating the visceral functions of the head and specific structures in the neck, thoracic, and abdominopelvic cavities. Preganglionic fibers of the parasympathetic division exit the brain through cranial nerves III (oculomotor), VII (facial), IX (glossopharyngeal), and X (vagus), delivering parasympathetic output to the respective visceral structures.
The vagus nerve (cranial nerve X) alone accounts for approximately 75...

The autonomic nervous system (ANS) is a critical component of the peripheral nervous system, primarily responsible for regulating involuntary bodily functions and maintaining homeostasis. It functions in tandem with the central nervous system (CNS) to seamlessly coordinate various physiological processes without the need for conscious control.
The ANS comprises two main divisions: the sympathetic and parasympathetic divisions. These divisions function antagonistically to maintain a dynamic...

Overview

Parasympathetic signaling plays a crucial role in regulating various physiological processes. It involves the release of acetylcholine (ACh) by parasympathetic neurons, which can have localized and short-lived effects. The majority of ACh released is rapidly inactivated at the synapse by the enzyme acetylcholinesterase (AChE), which hydrolyzes Ach into choline and acetate. Additionally, the tissue cholinesterase deactivates any ACh diffusing into the surrounding tissues.
The effects of...