Dopamine suppresses persistent firing in layer III lateral entorhinal cortex neurons. (1st May 2018)

• Record Type: Journal Article
• Authors: Batallán-Burrowes, Ariel A.; Chapman, C. Andrew
• Is Part Of: Neuroscience letters. Volume 674(2018)
• Page Start: 70
• Page End: 74
• Publication Date: 2018-05-01
• Subjects: Working memory -- Entorhinal cortex -- Persistent firing -- Acetylcholine -- Dopamine; Neurology -- Periodicals; Neurology -- Periodicals; Research -- Periodicals; Neurologie -- Périodiques; Neuroanatomie -- Périodiques; Neuropharmacologie -- Périodiques; Neurophysiologie -- Périodiques; Neurology; Periodicals; Electronic journals; 617.48
• DOI: 10.1016/j.neulet.2018.03.012
• Languages: English
• ISSNs: 0304-3940

Abstract

Highlights: Persistent firing was induced in 39% of layer III lateral entorhinal cortex neurons. Persistent firing was dependent on cholinergic receptor activation with carbachol. Dopamine suppressed the induction of persistent firing in carbachol. When observed in dopamine, the intensity of persistent firing was not significantly reduced. Abstract: Persistent firing in layer III entorhinal cortex neurons that can be evoked during muscarinic receptor activation may contribute to mechanisms of working memory. The entorhinal cortex receives strong dopaminergic inputs which may modulate working memory for motivationally significant information. We used whole cell recordings in in vitro rat brain slices to assess the effects of dopamine on persistent firing in layer III neurons initiated by depolarizing current injection. Persistent firing during pharmacological block of ionotropic excitatory and inhibitory synaptic transmission, and in the presence of the cholinergic agonist carbachol (10 μM), was observed in 39% of layer III pyramidal cells. Addition of 1 μM dopamine suppressed the incidence of persistent firing and similarly reduced the mean probability of induction of persistent firing at each current step, without significantly affecting the latency, duration, plateau potential, or frequency of persistent firing that was induced. These results indicate that dopamine can result in a suppression of the induction of persistent firing in layer III entorhinal neurons, while still being permissive of persistent firing once it is initiated.