While most users of the Brain Browser will probably consider themselves
neuroscientists, it would be  only ego-building to think that these peptides are
exclusively important for the nervous system.  In fact, the kinds of effects
regulated by peptides are also well recognized by scholars of the endocrine,
gastro-intestinal, and immune systems as well. The fact that cells of the nervous
system and of the immune system may each make and respond to  similar if not
identical peptides has generated a belief-- as yet unsubstantiated-- that the two
systems make also regulate each other, generating a possible new frontier of
neuroimmunology*.