ac6b03642_si_001.pdf (665.55 kB)
Platform to Enable Combined Measurement of Dopamine and Neural Activity
journal contribution
posted on 2017-02-17, 16:23 authored by Kate L. Parent, Daniel F. Hill, Lindsey M. Crown, Jean-Paul Wiegand, Kathleen F. Gies, Michael A. Miller, Christopher W. Atcherley, Michael L. Heien, Stephen L. CowenComplex behaviors
depend on the coordination of the activities
of ensembles of neurons and the release of neuromodulators such as
dopamine. The mechanisms underlying such coordination are not well-understood
due to a lack of instrumentation for combined and real-time monitoring
of neuromodulator release and the activities of large ensembles of
neurons. Here we describe a measurement platform that allows for the
combined monitoring of electrophysiology from a high-density electrode
array and dopamine dynamics from a carbon-fiber microelectrode. Integration
of these two measurement systems was achieved through modification
of the existing instrumentation. A shared grounded reference electrode
was used in both systems to minimize electrical interference. Further,
an optional solid-state-relay array positioned between the electrophysiological
electrode array and amplifiers was added to provide additional electrical
isolation. The capacity of the integrated measurement platform, termed
DANA (Dopamine And Neural Activity), to measure action potentials
(high frequency) and local-field oscillations (low frequency) was
characterized in vitro using an artificial cerebral
spinal fluid gelatin. In vivo recordings from the
DANA platform in anesthetized rats demonstrated the ability of the
system for near-simultaneous measurement of dopamine release and activity
from multiple neurons both in distant brain regions (striatum and
hippocampus) and within the same brain region (striatum). Furthermore,
this system was shown to be sufficiently compact to measure activity
in freely moving animals through recording of single-neuron activity,
high-frequency local-field oscillations, and dopamine release.