Ventrolateral preoptic nucleus
Encyclopedia
The ventrolateral preoptic nucleus (VLPO) is a group of neurons in the hypothalamus
. They are primarily active during Non-rapid eye movement sleep, and inhibit other neurons that are involved in wakefulness. The VLPO neurons release the inhibitory neurotransmitters galanin
and GABA
to inhibit the monaminergic cell groups in the locus coeruleus, the raphe nucleus, and the tuberomammillary nucleus
.
Hypothalamus
The Hypothalamus is a portion of the brain that contains a number of small nuclei with a variety of functions...
. They are primarily active during Non-rapid eye movement sleep, and inhibit other neurons that are involved in wakefulness. The VLPO neurons release the inhibitory neurotransmitters galanin
Galanin
Galanin is a neuropeptide encoded by the GAL gene, that is widely expressed in the brain, spinal cord, and gut of humans as well as other mammals. Galanin signaling occurs through three G protein-coupled receptors....
and GABA
Gabâ
Gabâ or gabaa, for the people in many parts of the Philippines), is the concept of a non-human and non-divine, imminent retribution. A sort of negative karma, it is generally seen as an evil effect on a person because of their wrongdoings or transgressions...
to inhibit the monaminergic cell groups in the locus coeruleus, the raphe nucleus, and the tuberomammillary nucleus
Tuberomammillary nucleus
The tuberomammillary nucleus is a subnucleus of the posterior third of the hypothalamus. It consists of, largely, histaminergic neurons and is involved with the control of arousal, sleep and circadian rhythm....
.
- VLPO is activated by somnogens, from which serotoninSerotoninSerotonin or 5-hydroxytryptamine is a monoamine neurotransmitter. Biochemically derived from tryptophan, serotonin is primarily found in the gastrointestinal tract, platelets, and in the central nervous system of animals including humans...
and adenosine accumulate during waking. Another VLPO-activating endosomnogen is prostaglandinProstaglandinA prostaglandin is any member of a group of lipid compounds that are derived enzymatically from fatty acids and have important functions in the animal body. Every prostaglandin contains 20 carbon atoms, including a 5-carbon ring....
D2. - VLPO is inhibited by arousalArousalArousal is a physiological and psychological state of being awake or reactive to stimuli. It involves the activation of the reticular activating system in the brain stem, the autonomic nervous system and the endocrine system, leading to increased heart rate and blood pressure and a condition of...
transmitters noradrenaline and acetylcholineAcetylcholineThe chemical compound acetylcholine is a neurotransmitter in both the peripheral nervous system and central nervous system in many organisms including humans...
.