Dopamine Modulates Excitatory Synaptic Transmission by Activating Presynaptic D1-like Dopamine Receptors in the RA Projection Neurons of Zebra Finches

Songhua Wang; Shaoyi Liu; Qingqin Wang; Yalun Sun; Lihua Yao; Dongfeng Li; Wei Meng

doi:10.3389/fncel.2020.00126

Dopamine Modulates Excitatory Synaptic Transmission by Activating Presynaptic D1-like Dopamine Receptors in the RA Projection Neurons of Zebra Finches

Front Cell Neurosci. 2020 May 12:14:126. doi: 10.3389/fncel.2020.00126. eCollection 2020.

Authors

Songhua Wang¹, Shaoyi Liu², Qingqin Wang¹, Yalun Sun¹, Lihua Yao³, Dongfeng Li², Wei Meng¹

Affiliations

¹ Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, Nanchang, China.
² School of Life Science, South China Normal University, Guangzhou, China.
³ School of Life Science, Jiangxi Science and Technology Normal University, Nanchang, China.

Abstract

Songbirds are useful vertebrate study models for vocal learning and memory. The robust nucleus of the arcopallium (RA) receives synaptic inputs from both the posterior and anterior pathways of the song control system in songbirds. Hence, RA plays an important role in the control of singing. RA receives dopaminergic (DArgic) inputs that increase the excitability of RA projection neurons (PNs). However, the effects of DA on excitatory synaptic transmission are yet to be deciphered. In this study, the effects of DA on the excitatory synaptic transmission of the PNs in the RA of adult male zebra finches were investigated using a whole-cell patch-clamp recording. We observed that DA decreased the frequency of spontaneous excitatory postsynaptic currents (sEPSCs) and miniature excitatory postsynaptic currents (mEPSCs). The effects of DA were mimicked by the D1-like DA receptor (D1R) agonist, SKF-38393, but not the D2-like DA receptor (D2R) agonist, Quinpirole. Also, the effects of DA were blocked by D1R antagonist, SCH-23390, but not the D2R antagonist, Sulpiride. These results demonstrate that DA modulates excitatory synaptic transmission by acting on D1R in the RA of adult male zebra finches.

Keywords: D1-like dopamine receptors; dopamine; excitatory synaptic transmission; the robust nucleus of the arcopallium; zebra finch.