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There are 4 glossary search results for:   neurotransmitters




Abbreviation:
ACh

Definition:
Acetylcholine (ACh) is a chemical neurotransmitter used by the central nervous system (CNS) as well as the peripheral nervous system (PNS). Acetylcholine is a classical neurotransmitter and, in fact, it was the first of the classic neurotransmitters to be discovered. It was discovered in 1914 by Henry Hallett Dale while conducting experiments on the heart.

Acetylcholine is the neurotransmitter used by the somatic division of the nervous system at the neuromuscular junction (where a somatic motor neuron makes synaptic contact with a skeletal muscle cell). Acetylcholine is also used extensively by both branches of the autonomic nervous system; sympathetic and parasympathetic. It is the primary neurotransmitter released in autonomic ganglia by preganglionic autonomic neurons. It is also the primary neurotransmitter released by parasympathetic postganglionic neurons. A few sympathetic postganglionic neurons also release acetylcholine. The diverse actions of acetylcholine are exerted via the activation of nicotinic and muscarinic ACh receptors.

Other resources:
Acetylcholine (Wikipedia)



Definition:
Neurohormones are chemical messenger molecules that are released by neurons, but enter the bloodstream where they travel to distant target sites within the body. Therefore, neurohormones share characteristics with both neurotransmitters and hormones. Similar to neurotransmitters, neurohormones are released by neurons. Similar to hormones, neurohormones travel in the bloodstream.

Two well-known examples of neurohormones are oxytocin and the antidiuretic hormone (also referred to as vasopressin).

Related glossary terms/phrases:
Hormone
Neurotransmitter



Definition:
Chemical messenger molecules released by neurons into the synaptic cleft.

Neurotransmitter molecules may be small molecules such as glutamate, γ-aminobutyric acid (GABA), acetylcholine, dopamine, norepinephrine, serotonin (5-hydroxytryptamine), and glycine. These are referred to as classic neurotransmitters. A neuron generally releases only one type of small classic neurotransmitter.

Neurotransmitters may also be peptide molecules, such as substance P, opioids, and somatostatin. These are referred to as neuropeptides.

Gas molecules, such as nitric oxide (NO), may also act as neurotransmitters.



Abbreviation:
Na+

Definition:
The main cation (positively charged ion) of the extracellular fluid.

Sodium (Na+) plays an important role in several physiological processes such as the action potential of neurons and muscle cells, secondary active, sodium-coupled transport of ions, nutrients, neurotransmitters across the plasma membrane of cells, and many other processes.

The extracellular concentration of Na+ is about 145 mM. The intracellular concentration of Na+ is about 15 mM.









Posted: Sunday, March 31, 2013
Last updated: Friday, August 28, 2015