TY - JOUR T1 - Dopaminergic modulation of synaptic integration and firing patterns in the rat entopenduncular nucleus JF - The Journal of Neuroscience JO - J. Neurosci. DO - 10.1523/JNEUROSCI.0639-17.2017 SP - 0639-17 AU - Hagar Lavian AU - Mara Almog AU - Ravit Madar AU - Yocheved Loewenstern AU - Izhar Bar-Gad AU - Eitan Okun AU - Alon Korngreen Y1 - 2017/06/26 UR - http://www.jneurosci.org/content/early/2017/06/26/JNEUROSCI.0639-17.2017.abstract N2 - Dopamine is known to differentially modulate the impact of cortical input to the striatum between the direct and indirect pathways of the basal ganglia (BG). However, the role of extrastriatal dopamine receptors (DRs) in BG information processing is less clear. To investigate the role of extrastriatal DRs we studied their distribution and function in one of the output nuclei of the rodent's BG, the entopeduncular nucleus (EP). qRT-PCR indicated that all DR subtypes were expressed by EP neurons, suggesting that both D1-like receptors (D1LRs) and D2-like receptors (D2LRs) were likely to affect information processing in the EP. Whole-cell recordings revealed that striatal inputs to the EP were potentiated by D1LRs whereas pallidal inputs to the EP were depressed by D2LRs. Changes to paired-pulse ratio (PPR) of inputs to the EP suggested that dopaminergic modulation of striatal inputs is mediated by postsynaptic receptors, and that of GP evoked inputs are mediated by presynaptic receptors. We show that these changes in synaptic efficacy changed the information content of EP neuron firing. Overall, the findings suggest that the dopaminergic system affects the passage of feedforward information through the BG by modulating input divergence in the striatum and output convergence in the EP.SIGNIFICANCE STATEMENTThe entopeduncular nucleus (EP), one of the basal ganglia (BG) output nuclei, is an important station in BG information processing. However, it remains unclear how EP neurons encode information, and how dopamine affects this process. This contrasts with the well-established role of dopamine in the striatum which is known to redistribute cortical input between the direct and indirect pathways. Here we show that in symmetry with the striatum, dopamine controls the rebalancing of information flow between the two pathways in the EP. Specifically, we demonstrate that dopamine modulates EP activity by modulating striatal and pallidal GABAergic inputs. These results call for a reassessment of current perspectives on BG information processing by highlighting the functional role of extrastriatal dopamine receptors. ER -