Evidence that substance-P receptors do not exist in mouse parotid and submandibular acinar cells.

Substance P (SP) had no effect on cytosolic Ca2+ concentration ([Ca2+]i) and inositol phosphate formation in mouse parotid and submandibular acinar cells, but induced a rapid increase in [Ca2+]i and production of inositol phosphates in rat acinar cells. In addition, SP did not stimulate amylase release from mouse parotid acini, but SP-induced amylase release was seen in rats. These results indicate that the mouse lacks SP receptors on parotid and submandibular acinar cells.