Human body from organs to the cells of which they are composed. The human body consists of many interacting systems of organs. These interact to maintain homeostasis, keeping the body in a stable state with safe levels of substances such as sugar and oxygen in the blood. Each system contributes to homeostasis, of itself, other systems, and the entire body. Some combined systems are referred to by joint names. For example, the nervous system and the endocrine system operate together as the neuroendocrine system. The nervous system receives information from the body, and transmits this to the brain via nerve impulses and
Satellite glial cell tumor necrosis factor α (TNFα) are other cellular factors that work to sensitize neurons to pain. SGCs are present in the PNS in fewer numbers than other more well-known types of glial cells, like astrocytes, but have been determined to affect nociception because of some of their physiological and pharmacological properties. In fact, just like astrocytes, SGCs have the ability to sense and regulate neighboring neuronal activity. First, after a period of nerve cell injury, SGCs are known to up-regulate GFAP and to undergo cell division. They have the ability to release chemoattractants, which are analogous to those released by