Orexinergic input to dopaminergic neurons of the human ventral tegmental area.
The mesolimbic reward pathway arising from dopaminergic (DA) neurons of the ventral tegmental area (VTA) has been strongly implicated in reward processing and drug abuse. In rodents, behaviors associated with this projection are profoundly influenced by an orexinergic input from the lateral hypothal...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Public Library of Science (PLoS)
2013-01-01
|
| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC3869755?pdf=render |
| _version_ | 1828395448414502912 |
|---|---|
| author | Erik Hrabovszky Csilla S Molnár Beáta Á Borsay Péter Gergely László Herczeg Zsolt Liposits |
| author_facet | Erik Hrabovszky Csilla S Molnár Beáta Á Borsay Péter Gergely László Herczeg Zsolt Liposits |
| author_sort | Erik Hrabovszky |
| collection | DOAJ |
| description | The mesolimbic reward pathway arising from dopaminergic (DA) neurons of the ventral tegmental area (VTA) has been strongly implicated in reward processing and drug abuse. In rodents, behaviors associated with this projection are profoundly influenced by an orexinergic input from the lateral hypothalamus to the VTA. Because the existence and significance of an analogous orexigenic regulatory mechanism acting in the human VTA have been elusive, here we addressed the possibility that orexinergic neurons provide direct input to DA neurons of the human VTA. Dual-label immunohistochemistry was used and orexinergic projections to the VTA and to DA neurons of the neighboring substantia nigra (SN) were analyzed comparatively in adult male humans and rats. Orexin B-immunoreactive (IR) axons apposed to tyrosine hydroxylase (TH)-IR DA and to non-DA neurons were scarce in the VTA and SN of both species. In the VTA, 15.0±2.8% of TH-IR perikarya in humans and 3.2±0.3% in rats received orexin B-IR afferent contacts. On average, 0.24±0.05 and 0.05±0.005 orexinergic appositions per TH-IR perikaryon were detected in humans and rats, respectively. The majority (86-88%) of randomly encountered orexinergic contacts targeted the dendritic compartment of DA neurons. Finally, DA neurons of the SN also received orexinergic innervation in both species. Based on the observation of five times heavier orexinergic input to TH-IR neurons of the human, compared with the rat, VTA, we propose that orexinergic mechanism acting in the VTA may play just as important roles in reward processing and drug abuse in humans, as already established well in rodents. |
| first_indexed | 2024-12-10T08:13:04Z |
| format | Article |
| id | doaj.art-fc77d88b89e34e1488832dfd542c536e |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-10T08:13:04Z |
| publishDate | 2013-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-fc77d88b89e34e1488832dfd542c536e2022-12-22T01:56:32ZengPublic Library of Science (PLoS)PLoS ONE1932-62032013-01-01812e8302910.1371/journal.pone.0083029Orexinergic input to dopaminergic neurons of the human ventral tegmental area.Erik HrabovszkyCsilla S MolnárBeáta Á BorsayPéter GergelyLászló HerczegZsolt LipositsThe mesolimbic reward pathway arising from dopaminergic (DA) neurons of the ventral tegmental area (VTA) has been strongly implicated in reward processing and drug abuse. In rodents, behaviors associated with this projection are profoundly influenced by an orexinergic input from the lateral hypothalamus to the VTA. Because the existence and significance of an analogous orexigenic regulatory mechanism acting in the human VTA have been elusive, here we addressed the possibility that orexinergic neurons provide direct input to DA neurons of the human VTA. Dual-label immunohistochemistry was used and orexinergic projections to the VTA and to DA neurons of the neighboring substantia nigra (SN) were analyzed comparatively in adult male humans and rats. Orexin B-immunoreactive (IR) axons apposed to tyrosine hydroxylase (TH)-IR DA and to non-DA neurons were scarce in the VTA and SN of both species. In the VTA, 15.0±2.8% of TH-IR perikarya in humans and 3.2±0.3% in rats received orexin B-IR afferent contacts. On average, 0.24±0.05 and 0.05±0.005 orexinergic appositions per TH-IR perikaryon were detected in humans and rats, respectively. The majority (86-88%) of randomly encountered orexinergic contacts targeted the dendritic compartment of DA neurons. Finally, DA neurons of the SN also received orexinergic innervation in both species. Based on the observation of five times heavier orexinergic input to TH-IR neurons of the human, compared with the rat, VTA, we propose that orexinergic mechanism acting in the VTA may play just as important roles in reward processing and drug abuse in humans, as already established well in rodents.http://europepmc.org/articles/PMC3869755?pdf=render |
| spellingShingle | Erik Hrabovszky Csilla S Molnár Beáta Á Borsay Péter Gergely László Herczeg Zsolt Liposits Orexinergic input to dopaminergic neurons of the human ventral tegmental area. PLoS ONE |
| title | Orexinergic input to dopaminergic neurons of the human ventral tegmental area. |
| title_full | Orexinergic input to dopaminergic neurons of the human ventral tegmental area. |
| title_fullStr | Orexinergic input to dopaminergic neurons of the human ventral tegmental area. |
| title_full_unstemmed | Orexinergic input to dopaminergic neurons of the human ventral tegmental area. |
| title_short | Orexinergic input to dopaminergic neurons of the human ventral tegmental area. |
| title_sort | orexinergic input to dopaminergic neurons of the human ventral tegmental area |
| url | http://europepmc.org/articles/PMC3869755?pdf=render |
| work_keys_str_mv | AT erikhrabovszky orexinergicinputtodopaminergicneuronsofthehumanventraltegmentalarea AT csillasmolnar orexinergicinputtodopaminergicneuronsofthehumanventraltegmentalarea AT beataaborsay orexinergicinputtodopaminergicneuronsofthehumanventraltegmentalarea AT petergergely orexinergicinputtodopaminergicneuronsofthehumanventraltegmentalarea AT laszloherczeg orexinergicinputtodopaminergicneuronsofthehumanventraltegmentalarea AT zsoltliposits orexinergicinputtodopaminergicneuronsofthehumanventraltegmentalarea |