Central/peripheral nervous system and immune responses

Maintenance of health is dependent on numerous regulatory interactions between organ systems. This review discusses interorgan communication between the nervous, endocrine, and immune systems and environmental and genetic influences on this neuroendocrine immune circuitry. Stresses of multiple types, including psychological and exposure to chemicals and infectious agents, may combine to enhance neuroimmunotoxicology. Altered nervous system functions can alter immunity which could result in exacerbation of infections, cancers or other immune-associated problems. Inversely, aberrant immune system activities could lead to pathologies associated with altered nervous activities, such as Alzheimer's disease, chronic fatigue, or multiple sclerosis. The nervous, endocrine and immune circuitry is multi-directional, and a chemical, physical or emotional stress could upset the homeostasis.