TITLE: Fiber Photometry on Noradrenergic/Dopaminergic Neurons (Open Field)
AUTHORS: Cristian González-Cabrera, Matthias Prigge

[DESCRIPTION]
The goal is to monitor in vivo calcium activity in noradrenergic and dopaminergic neurons within the hindbrain and midbrain of mice using fiber photometry during an open-field setup.

[STEPS]
SECTION: Pre-Experiment Preparation:
1. Animal Preparation:
SECTION: Pre-Experiment Preparation:
1.1. Ensure that the mice have undergone appropriate surgical procedures for fiber implantation and calcium indicator expression in the relevant brain region targeting catecholaminergic neurons. Allow for recovery and acclimatization.
SECTION: Pre-Experiment Preparation:
2. Equipment Setup:
SECTION: Pre-Experiment Preparation:
2.1. Start up the Doric fiber photometry system and ensure that the light source is connected to the appropriate fiber optic cable and that the photodetector is ready.
SECTION: Protocol Steps:
3. Equipment Initialization:
SECTION: Protocol Steps:
3.1. Turn on the System: Power on the Doric fiber photometry system.





SECTION: Protocol Steps:
3.2. Loading Configuration:
SECTION: Protocol Steps:
3.3. Open the data acquisition Doric software and load the appropriate experimental settings/configuration.
SECTION: Protocol Steps:
4. Measuring Power:
SECTION: Protocol Steps:
4.1. Measure the optical power at the tip of the fiber using the power meter.
SECTION: Protocol Steps:
4.2. Adjust the power output if necessary to ensure optimal excitation for the calcium indicator.
SECTION: Protocol Steps:
5. Bleaching the Fiber:
SECTION: Protocol Steps:
5.1. Immediately after verifying the power, bleach the fiber for a duration of 10 minutes at the desired excitation wavelength.
SECTION: Protocol Steps:
5.2. Ensure that the bleaching is uniform and that thermal management is maintained.
SECTION: Protocol Steps:
6. Connecting the Mouse:
SECTION: Protocol Steps:
6.1. Gently restrain the mouse and connect the custom patch cord to the implanted fiber and secure it appropriately. Note: Proper handling and acclimatization of the mouse prior to the experiment are essential to minimize stress and ensure reliable data collection. To mitigate stress, it is important to allow the mouse to become familiar with the experimental setting and equipment well ahead of the actual experiment. This can be achieved by gently handling the mouse for short periods over several days, providing a calm and quiet environment, and allowing the mouse to explore the open field arena before the actual recording. Also, proper handling techniques must be employed to minimize stress while connecting the patch cord to the mouse, as excessive restraint can lead to anxiety and impact the animal's physiological responses.
SECTION: Protocol Steps:
7. Recording:
SECTION: Protocol Steps:
7.1. Start the acquisition in the data acquisition software.
SECTION: Protocol Steps:
7.2. Monitor baseline calcium activity for an initial period (e.g., 1-2 minutes) before introducing any stimuli or behavioral tasks.
 

SECTION: Protocol Steps:
7.3. Conduct open-field experiments, allowing the mouse to explore freely for 5-30 minutes while recording calcium activity continuously.
SECTION: Protocol Steps:
8. Post-Experiment Procedures:
SECTION: Protocol Steps:
8.1. After completion of the recording session, disconnect the mouse from the patch cord carefully.
SECTION: Protocol Steps:
8.2. Return the mouse to its home cage for recovery or monitoring.
SECTION: Protocol Steps:
8.3. Save all data collected during the experiment for subsequent analysis.
SECTION: Protocol Steps:
9. Data Analysis: Analyse the collected data using pMAT or any other compatible software. pMAT is an open source Matlab-based code.
 
 https://github.com/djamesbarker/pMAT
SECTION: Notes:
11. This protocol outlines a general approach; adjustments may
be necessary based on specific experimental conditions or equipment
configurations.
SECTION: Notes:
10. It may be helpful to include video recordings to correlate behavioral data with calcium imaging results.