|Neuroendocrine cells release the chemical substances called hormones into blood, as they are triggered by receiving neurotransmitters from neurosecretory cells; this process is known as neuroendocrine integration. The crucial site of neuroendocrine integration is found in the hypothalamus and the pituitary gland. Hypothalamic neurosecretory cells release hormones in to the blood. Some of these hormones released at the hypothalamic median eminence which control the secretion of pituitary hormones, while others are released into the blood that show specific activity on vital organs or cells in the body. Pulmonary neuroendocrine cells are a kind of airway epithelial cells that are found as clusters called neuroepithelial bodies in the lungs. They were found since from neonatal stage in lungs airway. If a tumor forms in endocrine system, its secretions affect other parts of the body and cause serious illness. Some specialized neuroendocrine cells are found third ventricle in the brain they regulates functions in the entire body, like responses to sleep, reproductive system, stress and cold.