An anatomically distinct subpopulation of orexin neurons project from the lateral hypothalamus to the olfactory bulb
© 2023 Wiley Periodicals LLC..
Olfactory cues play a key role in natural behaviors such as finding food, finding mates, and avoiding predators. In principle, the ability of the olfactory system to carry out these perceptual functions would be facilitated by signaling related to an organism's physiological state. One candidate pathway includes a direct projection from the hypothalamus to the main olfactory bulb, the first stage of olfactory sensory processing. The pathway from the hypothalamus to the main olfactory bulb is thought to include neurons that express the neuropeptide orexin, although the proportion that is orexinergic remains unknown. A current model proposes that the orexin population is heterogeneous, yet it remains unknown whether the proportion that innervates the main olfactory bulb reflects a distinct subpopulation of the orexin population. Herein, we carried out combined retrograde tract tracing with immunohistochemistry for orexin-A in the mouse to define the proportion of hypothalamic input to the main olfactory bulb that is orexinergic and to determine what fraction of the orexin-A population innervates the bulb. The numbers and spatial positions of all retrogradely labeled neurons and all the orexin-A-expressing neurons were quantified in sequential sections through the hypothalamus. Retrogradely labeled neurons were found in the ipsilateral hypothalamus, of which 22% expressed orexin-A. The retrogradely labeled neurons that did and did not express orexin-A could be anatomically distinguished based on their spatial position and cell body area. Remarkably, only 7% of all the orexin-A neurons were retrogradely labeled, suggesting that only a small fraction of the orexin-A population directly innervate the main olfactory bulb. These neurons spatially overlapped with the orexin-A neurons that did not innervate the bulb, although the two cell populations were differentiated based on cell body area. Overall, these results support a model in which olfactory sensory processing is influenced by orexinergic feedback at the first synapse in the olfactory processing pathway.
| Medienart: |
E-Artikel |
|---|
| Erscheinungsjahr: |
2023 |
|---|---|
| Erschienen: |
2023 |
| Enthalten in: |
Zur Gesamtaufnahme - volume:531 |
|---|---|
| Enthalten in: |
The Journal of comparative neurology - 531(2023), 15 vom: 18. Okt., Seite 1510-1524 |
| Sprache: |
Englisch |
|---|
| Beteiligte Personen: |
Qi, Meizhu [VerfasserIn] |
|---|
| Links: |
|---|
| Anmerkungen: |
Date Completed 10.08.2023 Date Revised 21.01.2024 published: Print-Electronic Citation Status MEDLINE |
|---|
| doi: |
10.1002/cne.25518 |
|---|
| funding: |
|
|---|---|
| Förderinstitution / Projekttitel: |
|
| PPN (Katalog-ID): |
NLM359353215 |
|---|
| LEADER | 01000caa a22002652 4500 | ||
|---|---|---|---|
| 001 | NLM359353215 | ||
| 003 | DE-627 | ||
| 005 | 20240121231837.0 | ||
| 007 | cr uuu---uuuuu | ||
| 008 | 231226s2023 xx |||||o 00| ||eng c | ||
| 024 | 7 | |a 10.1002/cne.25518 |2 doi | |
| 028 | 5 | 2 | |a pubmed24n1266.xml |
| 035 | |a (DE-627)NLM359353215 | ||
| 035 | |a (NLM)37434469 | ||
| 040 | |a DE-627 |b ger |c DE-627 |e rakwb | ||
| 041 | |a eng | ||
| 100 | 1 | |a Qi, Meizhu |e verfasserin |4 aut | |
| 245 | 1 | 3 | |a An anatomically distinct subpopulation of orexin neurons project from the lateral hypothalamus to the olfactory bulb |
| 264 | 1 | |c 2023 | |
| 336 | |a Text |b txt |2 rdacontent | ||
| 337 | |a ƒaComputermedien |b c |2 rdamedia | ||
| 338 | |a ƒa Online-Ressource |b cr |2 rdacarrier | ||
| 500 | |a Date Completed 10.08.2023 | ||
| 500 | |a Date Revised 21.01.2024 | ||
| 500 | |a published: Print-Electronic | ||
| 500 | |a Citation Status MEDLINE | ||
| 520 | |a © 2023 Wiley Periodicals LLC. | ||
| 520 | |a Olfactory cues play a key role in natural behaviors such as finding food, finding mates, and avoiding predators. In principle, the ability of the olfactory system to carry out these perceptual functions would be facilitated by signaling related to an organism's physiological state. One candidate pathway includes a direct projection from the hypothalamus to the main olfactory bulb, the first stage of olfactory sensory processing. The pathway from the hypothalamus to the main olfactory bulb is thought to include neurons that express the neuropeptide orexin, although the proportion that is orexinergic remains unknown. A current model proposes that the orexin population is heterogeneous, yet it remains unknown whether the proportion that innervates the main olfactory bulb reflects a distinct subpopulation of the orexin population. Herein, we carried out combined retrograde tract tracing with immunohistochemistry for orexin-A in the mouse to define the proportion of hypothalamic input to the main olfactory bulb that is orexinergic and to determine what fraction of the orexin-A population innervates the bulb. The numbers and spatial positions of all retrogradely labeled neurons and all the orexin-A-expressing neurons were quantified in sequential sections through the hypothalamus. Retrogradely labeled neurons were found in the ipsilateral hypothalamus, of which 22% expressed orexin-A. The retrogradely labeled neurons that did and did not express orexin-A could be anatomically distinguished based on their spatial position and cell body area. Remarkably, only 7% of all the orexin-A neurons were retrogradely labeled, suggesting that only a small fraction of the orexin-A population directly innervate the main olfactory bulb. These neurons spatially overlapped with the orexin-A neurons that did not innervate the bulb, although the two cell populations were differentiated based on cell body area. Overall, these results support a model in which olfactory sensory processing is influenced by orexinergic feedback at the first synapse in the olfactory processing pathway | ||
| 650 | 4 | |a Journal Article | |
| 650 | 4 | |a Research Support, U.S. Gov't, Non-P.H.S. | |
| 650 | 4 | |a Research Support, Non-U.S. Gov't | |
| 650 | 4 | |a Research Support, N.I.H., Extramural | |
| 650 | 4 | |a hypothalamus | |
| 650 | 4 | |a metabolism | |
| 650 | 4 | |a neuromodulation | |
| 650 | 4 | |a olfactory | |
| 650 | 4 | |a orexin | |
| 650 | 4 | |a retrograde tracer | |
| 650 | 4 | |a sensory processing | |
| 650 | 7 | |a Orexins |2 NLM | |
| 650 | 7 | |a Neuropeptides |2 NLM | |
| 700 | 1 | |a Fadool, Debra Ann |e verfasserin |4 aut | |
| 700 | 1 | |a Storace, Douglas A |e verfasserin |4 aut | |
| 773 | 0 | 8 | |i Enthalten in |t The Journal of comparative neurology |d 1945 |g 531(2023), 15 vom: 18. Okt., Seite 1510-1524 |w (DE-627)NLM000357871 |x 1096-9861 |7 nnns |
| 773 | 1 | 8 | |g volume:531 |g year:2023 |g number:15 |g day:18 |g month:10 |g pages:1510-1524 |
| 856 | 4 | 0 | |u http://dx.doi.org/10.1002/cne.25518 |3 Volltext |
| 912 | |a GBV_USEFLAG_A | ||
| 912 | |a GBV_NLM | ||
| 951 | |a AR | ||
| 952 | |d 531 |j 2023 |e 15 |b 18 |c 10 |h 1510-1524 | ||