Neurogenic switching is proposed as a hypothesis for a mechanism by which a stimulus at one site can lead to inflammation at a distant site. Neurogenic inflammation occurs when substance P and other neuropeptides released from sensory neurons produce an inflammatory response, whereas immunogenic inflammation results from the binding of antigen to antibody or leukocyte receptors. There is a cros...

The combination of vasodilation and protein extravasation following activation of nociceptors has been termed "neurogenic inflammation." In contrast to rodents, no neurogenic protein extravasation can be elicited in healthy human skin. Dermal microdialysis has considerably increased our knowledge about neurogenic inflammation in human skin, including the involvement of mast cells.

Neurogenic inflammation as a pathway distinct from antigen-driven, immune-mediated inflammation may play a pivotal role in understanding a broad class of environmental health problems resulting from chemical exposures. Recent progress in understanding the mediators, triggers, and regulation of neurogenic inflammation is reviewed. Evidence for and speculations about a role for neurogenic inflamm...

William Meggs's recent article, "Neuro-genic Inflammation and Sensitivity to Environmental chemicals" (EHP 101:234-238), provides a useful introduction to a rapidly growing area of knowledge in physiology and posits a number of interesting hypotheses regarding the health effects of airborne chemicals. Some specific technical points, however, merit comment. Meggs describes the common chemical se...