Multi-dimensional oscillatory activity of mouse GnRH neurons in vivo

The gonadotropin-releasing hormone (GnRH) neurons represent the key output cells of the neural network controlling mammalian fertility. We used GCaMP fiber photometry to record the population activity of the GnRH neuron distal projections in the ventral arcuate nucleus where they merge before entering the median eminence to release GnRH into the portal vasculature. Recordings in freely behaving intact male and female mice revealed abrupt ~8-min duration increases in activity that correlated perfectly with the appearance of a subsequent pulse of luteinizing hormone (LH). The GnRH neuron dendrons also exhibited a low level of unchanging clustered, rapidly fluctuating baseline activity in males and throughout the estrous cycle in females. In female mice, a gradual increase in basal activity that exhibited ~80-min oscillations began in the afternoon of proestrus and lasted for 12 h. This was associated with the onset of the LH surge that ended several hours before the fall in GCaMP signal. ..., We used fiber photometry to record GCaMP fluorescence signal in freely behaving mice for 6 or 24 h periods using previously described methodology (Han, Kane et al. 2019, Han, Morris et al. 2023). This included a custom-built photometry system using Doric components (Doric Lenses, QC, Canada) and National Instrument data acquisition board (TX, USA) based on a previous design (Lerner, Shilyansky et al. 2015). Blue (465-490 nm) and violet (405 nm) LED lights were sinusoidally modulated at frequencies of 531 and 211 Hz respectively and were focused onto a single fiber optic connected to the mouse. The light intensity at the tip of the fiber was 30-80 microwatts. Emitted fluorescence signal from the brain was collected via the same fiber, passed through a 500-550 nm emission filter and focused onto a fluorescence detector (Doric, QC, Canada). The emissions were collected at 10 Hz and the two GCaMP6 emissions were recovered by demodulating the 465-490 nm signals (calcium-dependent) and 405 nm..., , # Multi-dimensional oscillatory activity of mouse GnRH neurons in vivo

[https://doi.org/10.5061/dryad.pnvx0k6zr](https://doi.org/10.5061/dryad.pnvx0k6zr)

## Description of the data and file structure

Description of the data and file structure.

We have submitted 5 Excel files in total corresponding to figures 2-6  in the paper. Each figure has one Excel sheet with panels corresponding to each tab. For example, file Elife_GnRH_Fig2 Tab Fig2C corresponds to Fig 2C in the original article.

More details of data collection and analysis can be found in the figure legends and Methods section of the original article.

Applicable for all Species: mice

Missing values are listed as blank;

All data are plotted and analyzed using Graphpad Prism 10 as described in Methods section.

### Files and variables

#### File: Elife\_GnRH\_Fig2.xlsx

Tab A: Figure 2A. A representative example of 24-h GCaMP photometry recording. Column A:Time in minutes, Column B: Clock time (24h), Column C: deltaF/F in p...