Figure 1. Mechanisms of homeostatic regulation of SFO^Nos1 neurons.

a, Schematic of fiber photometry setup (scale bar, 100 µm). b, SFO^Nos1 neurons are activated by injection of NaCl. c, Angiotensin blockers (INH) do not abolish the response to NaCl. d, SFO^Nos1 neurons are similarly activated by equiosmotic mannitol and NaCl. e, SFO^Nos1 neurons are activated by injection of PEG. f, Angiotensin blockers abolish the this response. g, SFO^Nos1 neurons are activated by injection of isoproterenol. h, Angiotensin blockers abolish the this response. i, Schematic summarizing the mechanisms by which SFO^Nos1 neurons monitor the blood. Statistical analyses are described in Methods and in Extended Data Table 1. n = 5 mice for all experiments.