Open AccessDifferential electrophysiological properties of D1 and D2 spiny projection neurons in the mouse nucleus accumbens core
Author(s) -
Almuhtasib Nour,
Forcelli Patrick A.,
Vicini Stefano
Publication year - 2018
Publication title -
physiological reports
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.918
H-Index - 39
ISSN - 2051-817X
DOI - 10.14814/phy2.13784
Subject(s) - medium spiny neuron , nucleus accumbens , neuroscience , striatum , indirect pathway of movement , electrophysiology , ventral striatum , dopamine , dopamine receptor d2 , direct pathway of movement , excitatory postsynaptic potential , antidromic , chemistry , biology , inhibitory postsynaptic potential
The striatum consists of the dorsal (caudate/putamen) and the ventral (nucleus accumbens) regions. The nucleus accumbens is further divided into a core and shell. Both the dorsal and ventral striatum contain populations of spiny projection neurons, which make up 95% of the neurons within the striatum. SPN s are canonically categorized into those that express the D1‐type dopamine receptor (D1 SPN s) and those that express the D2‐type dopamine receptor (D2 SPN s). D1 and D2 SPN s differ with respect to both synaptic inputs and projection targets. In the dorsal striatum, it is well established that these populations of SPN s differ in terms of their electrophysiological and morphological properties. However, there remains a gap in our knowledge of the electrophysiological properties of SPN s in the nucleus accumbens core. To evaluate the differential properties of these SPN s, we performed whole‐cell recordings from D1 and D2 SPN s in BAC transgenic mice in which D1 SPN s fluoresce red and D2 SPN s fluoresce green. The two SPN subtypes did not differ in terms of their time constant, capacitance, resting membrane potential, or tonic current. However, D2 SPN s displayed heightened inhibitory postsynaptic current ( IPSC ) and miniature excitatory PSC frequency as compared with D1 SPN s. Furthermore, D2 SPN s displayed decreased rheobase, increased excitability as measured by firing rates to depolarizing current injections, increased inward rectification, increased input resistance, and decreased dendritic complexity compared to D1 SPN s. Our results demonstrate a dichotomy in the electrophysiological properties of D1 and D2 SPN s in the nucleus accumbens core, which contributes to our knowledge of ventral striatal circuitry.