Chronic inflammation begins the same way as acute inflammation. Fibroblasts respond to injury or infection by stopping their usual function of tissue maintenance and repair. They transform in shape and produce inflammatory chemicals TNF-α, IL-1α, IL-1β, IL-6, IL-12. For a number of reasons, including overwhelming infection, extensive tissue damage, inadequate immune response, this does result in an anti-inflammatory response. Nerve cells in the pain circuit, start firing in a more intense and rapid manner. Long Tern Potentiation starts and local astrocytes and microglia produce their own inflammatory cascade. This keeps LTP going and the nerve cells produce more Substance-P. 20% is sent out of nerve endings and expands the pain circuit Map. More nerve cells are taken from other jobs to create more pain. 80% of the increased Substance-P is sent down nerve axons backwards through synapses and is released into already inflamed tissue. This dramatically increases local inflammatory responses and overwhelms any chance of establishing and anti-inflammatory response. This process sets up a vicious circle between brain and body.