Healing

== Tissue damaged by inflammation ==
After inflammation has damaged tissue (when combatting bacterial infection for example) and pro-inflammatory [[eicosanoid]]s have completed their function, healing proceeds in 4 phases.<ref>''The Anti-Inflammation Zone'', Barry Sears, pages 230-233, 2005.</ref>

===Recall phase===
In the recall phase the [[adrenal gland]]s increase production of [[cortisol]] which shuts down eicosanoid production and inflammation.{{Citation needed|date=May 2022}}

===Resolution phase===
In the Resolution phase, pathogens and damaged tissue are removed by [[macrophage]]s (white blood cells). Red blood cells are also removed from the damaged tissue by macrophages. Failure to remove all of the damaged cells and pathogens may retrigger inflammation. The two subsets of macrophage M1 & M2 plays a crucial role in this phase, M1 macrophage being a pro inflammatory while as M2 is a regenerative and the plasticity between the two subsets determine the tissue inflammation or repair.{{Citation needed|date=May 2022}}

===Regeneration phase===
In the Regeneration phase, blood vessels are repaired and new cells form in the damaged site similar to the cells that were damaged and removed.  Some cells such as neurons and muscle cells (especially in the heart) are slow to recover.{{Citation needed|date=May 2022}}

===Repair phase===
In the Repair phase, new tissue is generated which requires a balance of anti-inflammatory and pro-inflammatory eicosanoids.  Anti-inflammatory eicosanoids include [[lipoxin]]s, [[epi-lipoxin]]s, and [[resolvin]]s, which cause release of growth hormones.{{Citation needed|date=May 2022}}