In this study, we investigated whether sphingosine-1-phosphate, furosemide, and indomethacin affect mucin release from airway goblet cells. Confluent primary hamster tracheal surface epithelial cells were metabolically radiolabeled and chased for 30 min or 24 hr in the presence of varying concentrations of the above agents to assess the effects on 3H-mucin release. Sphingosine-1-phosphate stimulated mucin release during 30 min of treatment period in a dose-dependent manner. However, furosemide and indomethacin showed no effect on both basal and stimulated mucin release during 30 min or 24 hr of treatment period. We conclude that sphingosine-1-phosphate can affect mucin release by directly acting on airway mucin-secreting cells.