PAIN AND TENDERNESS IN HUMAN TEMPORAL MUSCLE INDUCED BY BRADYKININ AND 5-HYDROXYTRYPTAMINE

Pain was induced in 19 healthy individuals by double-blind injections into the temporal muscle of 0.2 ml of physiological saline with or without active substances added. 5-Hydroxytryptamine (2 nmol) caused pain similar to saline, bradykinin (2 nmol) only insignificantly more pain (0.05 < p < 0.1), while a mixture of the two substances in half dosage (1 nmol + 1 nmol) caused pain significantly above saline (p < 0.01). Variations in the response to saline did not permit a conclusion to be made on the question of induced tenderness. However, the mixture of the two substances appeared to lower the pressure-pain threshold as measured by pressure algometer (p < 0.05).