Fig. 5.

(a) Identification of CRH neurons expressing GCaMP6s in the hypothalamic PVN of the hypothalamus of a mouse, and location of implanted fiber optical probe, 3V: third ventricle. The PVN is the cluster of fluorescent cells outlined in the micrograph for # 1. Scale bars: #1 $100\mu \mathrm{m}$, #2 to 6 $200\mu \mathrm{m}$ (b) $\mathrm{\Delta }F$ corrected for radial and axial probe misalignment using experimentally validated theoretical models of fluorescence detection in each animal.