NIH Director's Seminar Series presents "Long-range synaptic and local receptor-mediated control of dopaminergic neuron excitability – dendrites, soma and axons "

Friday, June 17, 2022 | 12:00 - 1:00 PM

Remote Access

https://videocast.nih.gov/watch=45656

Individuals with disabilities who need sign language interpreters and/or reasonable accommodations to participate in this event should contact Margaret McBurney at 301-496-1921 or mmcburney@od.nih.gov .


Background

Dopamine-releasing neurons located in the midbrain play a central role in reward and motor learning behaviors. Their dysfunction is implicated in an array of disorders from addiction to Parkinson’s Disease (PD). The Cellular Neurophysiology Section headed by Dr. Zayd Khaliq examines the circuit, synaptic and intrinsic mechanisms that contribute to the firing patterns that underlie dopamine-dependent behaviors.


Lecture

The first part of the lecture will discuss the ionic and modulatory mechanisms of firing patterns observed in dopaminergic neurons of the substantia nigra during aversive behaviors. Axons of dopaminergic neurons transmit reinforcement signals to the striatum through patterns of propagating action potentials. Within the striatum, dopaminergic axons receive direct input from the local striatal circuit via receptor-mediated conductances that can directly influence axonal excitability and dopamine release.

In the second part of this lecture, Dr. Khaliq will discuss his lab’s recent findings examining how dopamine signaling within the striatum can occur independently of somatic firing activity and the mechanisms by which local receptors shape the subthreshold membrane potential of dopaminergic axons, propagated firing, and ultimately striatal dopamine release. The experiments in Dr. Khaliq’s lab use a combination of approaches including advanced electrophysiology, calcium imaging, optogenetic actuators and sensors, anatomical approaches and analysis, transgenic animals and animal behavior.