The sleep-promoting ventrolateral preoptic nucleus is organized into two functionally distinct compartments

In P30 Gal-GFP mice, euthanized at ZT4, confocal profiles of neuronal (Gal-GFP, NeuN), synaptic (VGAT, gephyrin), astrocytic (Sox9, Cx30), and activity (c-Fos) fluorescent markers were measured in the center of the VLPO, from the pia to 260 µm, and fitted with a two-segment piecewise linear model. </p><p dir="ltr">In the connected article, we found that all neuronal and astroglial markers decline with depth, with a mean inflection point at 98 ± 8 µm, defining a superficial Compartment I and a deeper Compartment II.

Electrophysiological recordings further reveal compartment-specific differences in neuronal excitability and synaptic input, with intrinsic properties varying progressively with depth. Synaptic input shows a step-like transition between compartments. Spike-generation properties are conserved.</p><p dir="ltr">The linked set contains a data table of galaninergic fluorescence (Input_Matrix.xlsx) across distance (the pial surface to 206 µm) and the MATLAB script (fit_piecewise_linear_0.m) to run the piecewise fit model, as well as the script to generate the figure as % max intensity (run_real_data_GFP_center_max.m).</p><p dir="ltr"><br></p>