New discoveries by scientists at King's College London about the nature of pain may lead to improved methods for treatment. Researchers have discovered how heat causes pain by sending an electric current into pain-sensitive nerves. They have learned that a chemical called bradykinin, which is found in damaged or inflamed tissue, is essential in the body's response to pain. An enzyme called kinase C was activated in nerve cells by the bradykinin and was responsible for greater pain when the heat stimulus was applied repeatedly.