TY - JOUR
T1 - In Vivo Ambient Serotonin Measurements at Carbon-Fiber Microelectrodes
AU - Abdalla, Aya
AU - Atcherley, Christopher W.
AU - Pathirathna, Pavithra
AU - Samaranayake, Srimal
AU - Qiang, Beidi
AU - Peña, Edsel
AU - Morgan, Stephen L.
AU - Heien, Michael L.
AU - Hashemi, Parastoo
N1 - Funding Information:
The authors would like to thank Kevin Wood, Anisa Zeqja, Matthew Jackson, Megan Connolly, and Thushani Siriward-hane for experimental assistance and helpful conversations. The University of South Carolina start-up funds (P.H.), the Eli Lily Young Investigator Award (P.H.), NIH (MH106563) (P.H.), and NIH (DA034975) (M.L.H.) funded this research. Portions of the statistical analysis were provided by the Biometry Core of the Center for Colon Cancer Research under NIH support P30GM103336-01A1.
Publisher Copyright:
© 2017 American Chemical Society.
PY - 2017/9/19
Y1 - 2017/9/19
N2 - The mechanisms that control extracellular serotonin levels in vivo are not well-defined. This shortcoming makes it very challenging to diagnose and treat the many psychiatric disorders in which serotonin is implicated. Fast-scan cyclic voltammetry (FSCV) can measure rapid serotonin release and reuptake events but cannot report critically important ambient serotonin levels. In this Article, we use fast-scan controlled adsorption voltammetry (FSCAV), to measure serotonin's steady-state, extracellular chemistry. We characterize the "Jackson" voltammetric waveform for FSCAV and show highly stable, selective, and sensitive ambient serotonin measurements in vitro. In vivo, we report basal serotonin levels in the CA2 region of the hippocampus as 64.9 ± 2.3 nM (n = 15 mice, weighted average ± standard error). We electrochemically and pharmacologically verify the selectivity of the serotonin signal. Finally, we develop a statistical model that incorporates the uncertainty in in vivo measurements, in addition to electrode variability, to more critically analyze the time course of pharmacological data. Our novel method is a uniquely powerful analysis tool that can provide deeper insights into the mechanisms that control serotonin's extracellular levels.
AB - The mechanisms that control extracellular serotonin levels in vivo are not well-defined. This shortcoming makes it very challenging to diagnose and treat the many psychiatric disorders in which serotonin is implicated. Fast-scan cyclic voltammetry (FSCV) can measure rapid serotonin release and reuptake events but cannot report critically important ambient serotonin levels. In this Article, we use fast-scan controlled adsorption voltammetry (FSCAV), to measure serotonin's steady-state, extracellular chemistry. We characterize the "Jackson" voltammetric waveform for FSCAV and show highly stable, selective, and sensitive ambient serotonin measurements in vitro. In vivo, we report basal serotonin levels in the CA2 region of the hippocampus as 64.9 ± 2.3 nM (n = 15 mice, weighted average ± standard error). We electrochemically and pharmacologically verify the selectivity of the serotonin signal. Finally, we develop a statistical model that incorporates the uncertainty in in vivo measurements, in addition to electrode variability, to more critically analyze the time course of pharmacological data. Our novel method is a uniquely powerful analysis tool that can provide deeper insights into the mechanisms that control serotonin's extracellular levels.
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U2 - 10.1021/acs.analchem.7b01257
DO - 10.1021/acs.analchem.7b01257
M3 - Article
C2 - 28795565
AN - SCOPUS:85029587735
SN - 0003-2700
VL - 89
SP - 9703
EP - 9711
JO - Analytical Chemistry
JF - Analytical Chemistry
IS - 18
ER -