Abstract
Involvement of both the serotonergic and the endogenous opioid systems in the onset of depressive behavior has been suggested. Previously we showed that serotonin (5-hydroxytryptamine) facilitates β-endorphin release in the nucleus accumbens (NAcc). Herein, the microdialysis method was used to assess in vivo the effects of serotonin on β-endorphin release in a rat model of depressive behavior (the Flinders sensitive line, FSL), before and after antidepressant treatment. The basal extracellular level of β-endorphin in the NAcc of FSL rats did not differ significantly from that in control rats. However, serotonin-induced β-endorphin release was impaired in FSL rats. Chronic treatment (18 days) with desipramine or paroxetine did not significantly affect the extracellular levels of β-endorphin in the NAcc of either the FSL or control rats. However, the chronic antidepressant treatment did normalize the serotonin-induced release of β-endorphin in FSL rats, as well as their behavioral manifestation of depressive behavior. Our results show that depressive behavior may relate to an impaired effect of serotonin on β-endorphin release in the NAcc in a rat model of depression, and suggest a possible new mode of action of antidepressant drugs.
| Original language | English |
|---|---|
| Pages (from-to) | 389-393 |
| Number of pages | 5 |
| Journal | Neuroscience |
| Volume | 110 |
| Issue number | 3 |
| DOIs | |
| State | Published - 20 Mar 2002 |
Bibliographical note
Funding Information:This study was in part funded by the National Institute of Psychobiology in Israel and the Israel Academy of Science and Humanities.
Funding
This study was in part funded by the National Institute of Psychobiology in Israel and the Israel Academy of Science and Humanities.
| Funders | Funder number |
|---|---|
| National Institute of Psychobiology in Israel | |
| Israel Academy of Sciences and Humanities |
Keywords
- Depression
- Microdialysis
- Nucleus accumbens
- Serotonin
- β-endorphin