Sodium (Na+) is an essential micronutrient that is required by all types of organisms. Therefore, a sufficient supply of sodium, paired with multiple tightly regulated mechanisms for maintaining homeostatic levels of the mineral is crucial for survival. Over the recent decades, different mechanisms that detect or modulate bodily sodium levels have been identified in both the central nervous system and in taste receptor cells of the gustatory system. However, little is known about the involvement of the gut as a potential sodium sensing and signaling organ. In this thesis, we study a novel post-ingestive sodium sensing mechanism that helps regulate precise sodium homeostasis. Behavioral assays and immunostaining methods have been used to elucidate the working mechanisms of such sodium sensors.