Only the salt-sensing brain cells get more active when salt is low—not other nearby cells—and they don’t get the signal from nerves in the gut, meaning they respond directly to hormones in the blood.
Scientific Claim
Sodium deficiency selectively increases the firing of NTSHSD2 neurons but not neighboring NTS neurons, and this activation is not mediated by vagal afferent input, indicating a cell-autonomous, hormone-driven mechanism.
Original Statement
“Na+ deficiency selectively increases the firing of NTSHSD2 neurons... Lack of vagal input to NTSHSD2 neurons is consistent with the previous finding that most NTSHSD2 neurons receive few or no close contacts from boutons labeled by biotinylated dextran amine injected into the nodose ganglia.”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
definitive
Can make definitive causal claims
Assessment Explanation
The study directly compares firing rates between NTSHSD2 and non-NTSHSD2 neurons and tests vagal connectivity using circuit mapping, providing clear evidence for selective, non-vagal activation.
Evidence from Studies
Supporting (1)
When your body needs salt, special brain cells called NTSHSD2 neurons turn on by themselves using internal switches, not because of signals from your nerves—this happens because of hormones, not because your stomach or gut is telling them to.