Substance P (7-11) increases PGE2 and collagenase production at concentrations greater than 1 μM. Substance P (7-11), but not intact SP, SP-(1-4), SP-(1-6), SP- (8-11) or SP-(9-1 1), nor the tachykinins NKA and NKB, causes an increase in the intracellular calcium concentration as measured by the fluorescent dye Fura-2. The maximal change in intracellular calcium induced by 10 μM Substance P (7-11) was 140±30 nM.