The effect on GI motility is probably peripheral. I don't know much about the peripheral effects of ghrelin, I'm afraid.
Here's a link to TZYM's Phase 2b results for their lead drug for POI: http://ir.tranzyme.com/releasedetail.cfm?ReleaseID=556399 . They are expecting pivotal Phase 3 results for this drug first half of this year. My expectations remain tempered for this lead drug due to the following: (1) limited success Entereg has had in POI; (2) TZYM's drug is an IV, not oral (like Entereg); and (3) they don't have any big name party on board (just a Euro company called Norgine that I don't know anything about).