Abstract
The dorsal half of the midbrain periaqueductal grey matter (dPAG) functions as a midbrain aversive system. Serotonin exerts anti-aversive effects in the dPAG that are mediated by actions at 5-hydroxytryptamine (5-HT)(1A)- and 5-HT(2A)-receptors. Since at the cellular level, 5-HT(2A)-receptor activation has been shown to evoke excitatory responses in the dPAG, it is possible that anti-aversive 5-HT(2A)-mediated effects are mediated indirectly by activation of inhibitory gamma-aminobutyric acid (GABA)ergic interneurones. In rats, immunoreactivity for 5-HT(2A)-receptors was present on the soma and dendrites of neurones throughout the PAG. Co-localization studies revealed that the majority (>90%) of 5-HT(2A)-receptor-labelled cells also showed immunoreactivity for GABA. These findings may provide an anatomical substrate for 5-HT(2A)-mediated anti-aversive effects in the dPAG.
| Original language | English |
|---|---|
| Pages (from-to) | 151-4 |
| Number of pages | 4 |
| Journal | Neuroscience Letters |
| Volume | 326 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 5 Jul 2002 |
Keywords
- gamma-aminobutyric acid interneurones
- periaqueductal grey matter
- aversion
- immunoreactivity
- 5-hydroxytryptamine(2A)-receptors