It was originally isolated from the mammalian small intestine amongst mammalian neurons called intramural neurons which function in the motor activity of the intestinal walls. An example of this was revealed in a study that demonstrated that this peptide regulates water and electrolyte transportation in the human jejunum; similar to its inhibitory effects on fluid absorption in the small intestine of pigs and rats.
This peptide was initially discovered in mammalian small intestine, alongside intramural neurons responsible for intestinal wall motor functions. A study has shown that this peptide controls water and electrolyte transport in human jejunum; similar to its inhibitory effect on fluid absorption in the intestines of pigs and rats.