DOI: 10.5061/dryad.jdfn2z3d9
title: Nitric oxide is not responsible for initial sensory-induced neurovascular coupling response in the barrel cortex of lightly anaesthetised mice

description: Significance: Neurovascular coupling matches changes in neural activity to
 localized changes in cerebral blood flow. Although much is known about the
 role of excitatory neurons in neurovascular coupling, that of
 inhibitory interneurons is unresolved. Although neuronal nitric oxide
 synthase (nNOS)-expressing interneurons are capable of eliciting
 vasodilation, the role of nitric oxide in neurovascular
 coupling is debated.Aim: We investigated the role of nitric oxide
 in hemodynamic responses evoked by nNOS-expressing interneurons
 and whisker stimulation in mouse sensory cortex.Approach: In lightly
 anesthetized mice expressing channelrhodopsin-2 in nNOS interneurons, 2D
 optical imaging spectroscopy was applied to measure stimulation-evoked
 cortical hemodynamic responses. To investigate the underlying vasodilatory
 pathways involved, the effects of pharmacological inhibitors of NOS and
 20-HETE were assessed.Results: Hemodynamic responses evoked by
 nNOS-expressing interneurons were altered in the presence of the NOS
 inhibitor LNAME, revealing an initial 20-HETE-dependent vasoconstriction.
 By contrast, the initial sensory-evoked hemodynamic response was largely
 unchanged.Conclusions: Our results challenge the involvement of
 nNOS-expressing interneurons and nitric oxide in the initiation of
 functional hyperemia, suggesting that nitric oxide may be involved in the
 recovery, rather than initiation, of sensory-induced hemodynamic
 responses.
description: # Nitric oxide is not responsible for initial sensory-induced
 neurovascular coupling response in the barrel cortex of lightly
 anaesthetised mice Dataset DOI:
 [10.5061/dryad.jdfn2z3d9](10.5061/dryad.jdfn2z3d9) Llywelyn Lee,
 University of Sheffield, United Kingdom.
 [llywelyn.lee@sheffield.ac.uk](mailto:llywelyn.lee@sheffield.ac.uk) Clare
 Howarth, University of Sheffield, United Kingdom.
 [c.howarth@sheffield.ac.uk](mailto:c.howarth@sheffield.ac.uk) Jason
 Berwick, University of Sheffield, United Kingdom.
 [j.berwick@sheffield.ac.uk](mailto:j.berwick@sheffield.ac.uk) Data were
 collected primarily by LL at the University of Sheffield. Data types are
 processed hemodynamic and electrophysiology data derived from *in vivo
 *mouse experiments using 2D-optical imaging spectroscopy and multichannel
 recording electrodes, respectively. Please refer to the associated
 manuscript for full details on data curation, processing and analysis.
 Hemodynamic data are presented as MATLAB files containing matrices of
 hemodynamic timeseries showing Hbt, Hbo and Hbr that have undergone
 spectral analysis, baseline adjustment for pharmacologically induced
 shifts, photostimulation artefact removal and trial averaging for each
 animal. Matrices are in the format (N animal x timepoint). For Figure 3
 the electrophysiology data are saved as a MATLAB file containing 2
 matrices, ‘tim_mu’ is the time vector (in seconds), the other matrix
 contains the evoked multi-unit activity in the format (electrode channel
 x   x timepoint). For Figure 7 the data file contains the results of the
 Fourier transform, provided as the frequency and associated power at that
 frequency in corresponding matrices. #### MATLAB Code The MATLAB script
 titled ‘plot_haem_timeseries’ plots the timeseries figures for figures
 1,2,4 and 5. The other MATLAB scripts plot the figures as they are titled.
 #### SPSS Files Each of the SPSS files contains the data used to generate
 the statistics for the metric named in each file. The type of test is
 described in the manuscript. #### Description of the data and file
 structure **Figure 1** * *MATLAB files*: Fig_1_LNAME_pre.mat,
 Fig_1_LNAME_post.mat- MATLAB matrices of hemodynamic timeseries, pre and
 post LNAME. Datasets are split into 6 matrices, by stimulation type
 (whisker and optogenetic) and hemodynamic measure (Hbo, Hbt, Hbr). Each
 matrix is in the format N animal x timepoint. * *SPSS files*:
 Fig1_LNAME_initialdip.sav, Fig1_LNAME_net_change.sav, Fig1_LNAME_peak.sav
 Data include animal number, presence of electrode, and results for Hbo,
 Hbt, Hbr for both stimulation types, pre and post LNAME. * *Excel file*:
 Fig1_LNAME.xlsx Same data with an extra column for sex of each animal.
 **Figure 2** * *MATLAB files*: Fig_2_LNAME_pre.mat, Fig_2_LNAME_Imm.mat,
 Fig_2_LNAME_Mid.mat, Fig_2_LNAME_post.mat-MATLAB matrices of hemodynamic
 timeseries at different timepoints before and after LNAME injection. Same
 structure as above, covering multiple timepoints before and after LNAME
 injection. * *SPSS file*: Fig2_LNAME_Timepoints_Hbt_initialdip.sav Data
 from the Hbt profile (optogenetic stimulation) at pre, Imm, and Mid
 timepoints. * *Excel file*: Fig2_LNAME_Timepoints.xlsx Same data as above.
 **Figure 3** * *MATLAB files*: MUA_opto_stim_pre_LNAME_fig3.mat,
 MUA_opto_stim_post_LNAME_fig3.mat, MUA_wh_stim_pre_LNAME_Fig3.mat,
 MUA_wh_stim_post_LNAME_fig3.mat. MATLAB matrices of multi-unit activity
 from optogenetic and whisker stimulations, pre and post LNAME MUA matrix:
 (electrode channel x Nanimal x timepoint), time vector: tim_mu (in
 seconds). * *SPSS file*: Fig3_MUA.sav Peak and mean MUA for both
 stimulations, pre and post-LNAMEE. * *Excel file*: Fig3_MUA.xlsx Same data
 as above. **Figure 4** * *MATLAB files*: Fig_4_NODRUG_pre.mat,
 Fig_4_NODRUG_post.mat Hemodynamic timeseries with no inhibitor.- MATLAB
 matrices of hemodynamic timeseries with no inhibitor applied, at the same
 pre+post timepoints * *SPSS files*: Fig4_NODRUG_Hbt_initialdip.sav,
 Fig4_NODRUG_Hbt_net_change.sav, Fig4_NODRUG_Hbt_peak.sav Metric results
 for Hbt, both stimulation types, at pre+post timepoints. * *Excel file*:
 Fig4_NODRUG.xlsx Same data as above. **Figure 5** * *MATLAB files*:
 Fig_5_HET_LNAME_pre.mat, Fig_5_HET_LNAME_post.mat MATLAB matrices of
 hemodynamic timeseries, pre and post simultaneous administration of
 HET0016 and LNAME * *SPSS files*: Fig5_HET_LNAME_Hbt_initialdip.sav,
 Fig5_HET_LNAME_Hbt_peak.sav Metric results for Hbt, both stimulation
 types, pre and post. * *Excel file*: Fig5_HET_LNAME.xlsx Same data as
 above. **Figure 6** * *MATLAB files*: Fig_6_LNAME_simultaneous_pre.mat,
 Fig_6_LNAME_simultaneous_post.mat Hemodynamic data for simultaneous
 (optogenetic + whisker) stimulation, pre and post LNAME. 9 matrices total.
 **Figure 7** * *MATLAB files*: Fig_7_LNAME_freq_power.mat,
 Fig_7_NODRUG_freq_power.mat 4 matrices total: 2 with frequencies (N animal
 x frequency), 2 with corresponding power (N animal x power). MATLAB
 matrices containing the results of the Fourier transform on the
 hemodynamic data at the pre+post timepoints, with LNAME application and
 with no inhibitor applied * *SPSS file*: Fig7_FFT_AUC.sav Area under the
 curve (AUC) from 0.09–0.11Hz. Factor: inhibitor presence (1 = no
 inhibitor, 2 = LNAME). * *Excel file*: Fig7_AUC.xlsx Same data as above.