SummaryPGE1 has been analyzed in terms of its effect on vagally driven gastric motor activity in dogs; profound inhibition of 2-deoxy-d-glucose stimulated motility was observed.The effect of PGE1 on serum calcium, potassium, and blood sugar levels has been monitored; no significant change in calcium or potassium during PGE1 infusion has been noted. Blood sugar, traditionally elevated by 2-deoxy- d-glucose, was not altered from its usual pattern after PGE1 infusion.PGE1 is capable, in doses previously shown to have an inhibitory effect on gastric secretion, to inhibit gastric motility as well. The precise mode of action is speculated upon but remains undisclosed.A special thanks is given to Miss Catherine Holm for her technical assistance and to Upjohn Company for the PGE1.