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| Brain: Ventral tegmentum | ||
|---|---|---|
| Transverse section of mid-brain at level of superior colliculi. (Tegmentum labeled at center right.) | ||
| NeuroNames | hier-512 | |
The ventral tegmentum or the ventral tegmental area (VTA) (tegmentum, Latin for covering) is part of the midbrain, lying close to the substantia nigra and the red nucleus. In latin tegmentum means "covering."
Contents |
Anatomy
According to Paxinos & Watson's atlas[1], the rat VTA is composed of the following nuclei:
- Paranigral nucleus
- Parabrachial pigmented nucleus
- Parainterfascicular nucleus (the homologue of human parapeduncular nucleus)
- Rostral ventral tegmental area
Pathways
The VTA consists of dopamine, GABA, and glutamate neurons, and is part of two major dopamine pathways:
- the mesolimbic pathway, which connects the VTA to the nucleus accumbens
- the mesocortical pathway, which connects the VTA to cortical areas in the frontal lobes.
Functions
The ventral tegmentum is considered to be part of the pleasure system, or reward circuit, one of the major sources of incentive and behavioural motivation. Activities that produce pleasure tend to activate the ventral tegmentum, and psychostimulant drugs (such as cocaine) directly target this area. Hence, it is widely implicated in neurobiological theories of addiction. Ibogaine, a psychoactive drug that reduces alcohol consumption, affects the glial cell line-derived neurotrophic factor (GDNF) in VTA.[2]
It is also shown to process various types of emotion and security motivation, where it may also play a role in avoidance and fear-conditioning.
Presence of Gap Junctions
The VTA has been shown to have a large network of GABAergic neurons that are interconnected via Gap junctions.
See also
- List of regions in the human brain
- dopamine
- mesocortical pathway
- mesolimbic pathway
- nucleus accumbens
References
- ^ Paxinos, G., & Watson, C. (2007). The Rat Brain in Stereotaxic Coordinates. New York: Academic Press, 6th ed
- ^ Sebastien Carnicella, Viktor Kharazia, Jerome Jeanblanc, Patricia H. Janak, Dorit Ron (June 2008). "GDNF is a fast-acting potent inhibitor of alcohol consumption and relapse". Proceedings of the National Academy of Sciences of the USA 105 (23): 8114-8119. doi:.
External links
- Oades R, Halliday G (1987). "Ventral tegmental (A10) system: neurobiology. 1. Anatomy and connectivity". Brain Res 434 (2): 117–65. PMID 3107759.
- Swanson, L.W. (1982). "The projections of the ventral tegmental area and adjacent regions: a combined fluorescent retrograde tracer and immunofluorescence study in the rat". Brain Res 9: 321–53. PMID 6816390.
- Yamaguchi T, Sheen W, and Morales M. (2007). "Glutamatergic neurons are present in the rat ventral tegmental area". Eur J Neuroscience 25: 106–118. doi:. PMID 17241272.
- Scripps Research article about Serotonin Receptors and Drug Abuse, regarding the serotonin-laden VTA.
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Wikipedia content modification information:
- This page was last modified on 11 October 2008, at 21:45.
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