Details

Autor(en) / Beteiligte

• Liu, Wei-Zhu
• Huang, Bo-Wei
• You, Wen-Jie
• Hu, Ping
• Wang, Xue-Hui
• Zhang, Jun-Yu
• Xu, Xiao-Bin
• Zhang, Zong-Yong
• Pan, Bing-Xing
• Zhang, Wen-Hua

Titel

Harmine enhances GABAergic transmission onto basoamygdala projection neurons in mice

Ist Teil von

• Brain research bulletin, 2018-03, Vol.137, p.294-300

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

2018

Link zum Volltext

Quelle

Elsevier ScienceDirect Journals Complete

Beschreibungen/Notizen

• •The anxiolytic effects of harmine have been found but the underlying mechanisms are largely unknown.•Harmine had no significant effects on glutamatergic transmission onto basal amygdala (BA) pyramidal neurons (PNs).•Harmine enhanced GABAergic transmission onto BA PNs through presynaptic mechanisms.•Harmine dramatically decreased the intrinsic excitability of BA PNs. Emerging evidence indicates that loss of inhibitory tone in amygdala with its subsequent overactivation contributes to the development of multiple mental disorders such as anxiety disorders and post-traumatic stress disorder (PTSD). Harmine is a member of natural β-carboline alkaloids which can readily cross the blood brain barrier and displays significant antidepressant and anxiolytic effects in rodents. However, the underlying neurobiological mechanisms are largely unknown. Here, by using whole-cell patch clamp recordings in in vitro amygdala slices, we examined the effect of harmine on glutamatergic and GABAergic transmission onto basal amygdala (BA) projection neurons (PNs). Our results showed that harmine affected neither the amplitude nor the frequency of spontaneous and miniature excitatory postsynaptic currents (sEPSCs/mEPSCs) of PNs. By contrast, it markedly increased both the amplitude and frequency of the spontaneous inhibitory postsynaptic currents (sIPSCs). For mIPSCs, only an increase of their frequency but not amplitude was observed following harmine perfusion, suggesting that harmine might act through presynaptic mechanism. In parallel, a reduction of paired-pulse ratio of evoked IPSCs emerged in the presence of harmine. Furthermore, the intrinsic excitability of PNs was dramatically decreased upon harmine treatment. Together, our study suggests that harmine selectively potentiates the inhibitory but not excitatory transmission onto BA PNs, which may contribute to its antidepressant and anxiolytic influence.