5-HT7 receptor increases gabaergic transmission in mouse basolateral amygdala

• Autorzy: Sowa J.E. , Kusek M. , Siwiec M. , Hess G. , Tokarski K.
• Języki publikacji: EN

Abstrakty

EN

The amygdala is a part of the limbic system involved in emotional processing, which is highly connected with other areas of the brain. Its basolateral region (BLA) re‑ ceives many inputs, including those from prefrontal cor‑ tex, hippocampus, and thalamus. Moreover, the amygdala receives robust innervation from the raphe nuclei. The last serotonin receptor to be discovered, 5-HT7, is highly expressed in the amygdala, suggesting a possibly strong influence on amygdala function. The 5-HT7 receptor is involved in modulation of many physiological processes, such as learning, pain sensation, and mood regulation. Functions of the 5-HT7 receptor at the cellular and net‑ work level have been studied in the hippocampus, dorsal raphe nuclei, and frontal cortex. However, very little is known about the physiological role of 5-HT7 receptors in the amygdala. Our study aimed to elucidate the effect of 5-HT7 receptor activation on synaptic transmission, elec‑ trophysiological properties, and excitability of neurons in the BLA. Whole-cell patch-clamp recordings were made primarily from principal neurons in the BLA of mice, using acute brain slices(300 μm). Afterrecording a baseline, 5-CT (250 nM) in the presence of WAY 100635 (2 µM), a 5-HT1A receptor antagonist, was bath-applied. Both inhibitory and excitatory synaptic transmission were measured by recording spontaneous (sIPSC/sEPSC), miniature (mIPSC/ mEPSC) or evoked (eEPSC/eIPSC) postsynaptic currents. Moreover, excitability, input resistance, and membrane voltage were measured. Specificity of the observed effects was further investigated using the same experimental protocols with the 5-HT7 antagonist SB269970. Our results show an increase in excitability in fast-spiking interneu‑ rons in the amygdala. Regarding inhibitory transmission, 5-HT7 activation increased the amplitude and frequency of spontaneous, but not miniature, IPSC in the principal cells, which suggests that this effect was network-dependent. These effects were abolished in the presence of the 5-HT7 antagonist SB269970. Our data suggest that 5-HT7 activa‑ tion increases GABAergic synaptic transmission onto BLA principal neurons. This is probably due to increased GABA release from local interneurons, where 5-HT7 receptors may be localized. Together, these results suggest that the 5-HT7 receptor may act as a potent modulator of BLA in‑ hibitory transmission. Supported by National Science Cen‑ tre, grant 2016/21/B/NZ4/03618.

• Wydawca: -
• Czasopismo: Acta Neurobiologiae Experimentalis
• Rocznik: 2018
• Tom: 78
• Numer: Suppl.1
• Opis fizyczny: p.12

Twórcy

autor

Sowa J.E.

• Department of Physiology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland

autor

Kusek M.

• Department of Physiology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland

autor

Siwiec M.

• Department of Physiology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland

autor

Hess G.

• Department of Physiology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
• Department of Neurophysiology and Chronobiology, Institute of Zoology, Jagiellonian University, Krakow, Poland

autor

Tokarski K.

• Department of Physiology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland