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Bernie - I find the article you posted called The Second Brain fascinating and intend to share it -- and try to discuss it -- with my neuro. Thanks for the information! Nancy Shlaes deGrazia (62/57) of Long Grove IL (formerly of Maplewood, New Jersey a suburb of Hoboken) "Bernard Barber,Ph.D." wrote: > Hi Phil, > > Good question . > > The Second Brain, by Michael Gershon, M.D.,Chairman Department of Anatomy > and Cell Biology at Columbia University in New York City,( a suburb of > Bayonne, N.J.) Published in 1998 by HarperCollins. > > We are having a cool 107 to day, in Phoenix, but the humidity is low, then > again an oven is an oven. > > Bernie > > At 12:26 AM 6/17/99 -0500, you wrote: > >I ran across some interesting information that is not particularly > >recent, but it is new to me and probably far less well known than > >it should be. I've written it up in the form of the article below. > >I hope you will find it interesting. Also, I would appreciate any > >further information anyone can offer on this subject. > > > >Phil Tompkins > >Hoboken NJ > >age 61/dx 1990 > > > >---------------------------------------------------------------- > > > > The Brain in the Gut and Parkinson's Disease > > > >Parkinson's disease (PD) is commonly defined as a degeneration of > >dopamine-producing neurons in the substantia nigra resulting in the > >primary symptoms of resting tremor, stiffness, bradykinesia, and poor > >balance. But there are numerous other symptoms of PD that seem > >remotely, if at all, related to the substantia nigra. These include > >such diverse phenomena as slowed emptying of the stomach contents > >into the small intestine, sexual impotence, sweating, and seborrhea. > >One may well wonder by what mechanism a deficiency of dopamine in the > >substantia nigra results in some of these other symptoms. > > > >Dopamine is produced and used elsewhere in the body besides in the > >substantia nigra. One such site is a vast neural network embedded in > >the gastrointestinal tract known as the enteric nervous system (ENS). > >It is becoming evident that the effects of PD on the involuntary > >functions of the gastrointestinal system are associated with > >degeneration of those dopamine-producing cells located not in the > >substantia nigra but rather in the ENS. The mechanism by which these > >effects are produced is unknown. However, evidence such as Lewy > >bodies in the enteric neurons and loss of dopaminergic neurons in the > >colon points to the involvement of the ENS in PD in a manner > >analogous to the involvement of the brain in PD. > > > >Gastrointestinal effects of PD attributable to the enteric system's > >involvement in the disease include reflux, delayed gastric > >emptying, and decreased motility. Swallowing difficulties and > >constipation, which have aspects falling under both voluntary and > >involuntary control, may be the result of PD in both the brain and > >the ENS. > > > >The ENS is located in the muscle and connective tissues that line > >the digestive organs. It contains some 100 million nerves cells, > >about the same number as are in the spinal chord. Many of its > >structures and chemicals parallel those of the brain, which it > >closely resembles at the cellular level. It has sensory and motor > >neurons, supportive glial cells, information processing circuits > >which transmit and process messages, and immune system cells. It > >has nearly every major substance found in the brain, including all > >the major neurotransmitters. Because of these resemblances, the > >ENS has been called a second brain, or "the brain in the gut." > > > >The ENS performs two major functions. First, it regulates the > >routine activity of the digestive system, by controlling the > >muscles which grind food in the stomach and move it through the > >digestive tract; and it regulates secretions which occur in > >the digestive tract. A particlar example of a control mechanism is > > >the feedback loop via which detection of fat in the small intestine > >prolongs retention in the stomach of its remaining contents. > > > >In its routine digestive role the ENS can operate quite > >independently of the central nervous system, being only fine-tuned > >by signals from the latter. > > > >The other major ENS function is to assist in preparing the organism > >for facing danger. Upon receipt of a "fight or flight" signal from > >the brain via the vagus nerve, the ENS activates "canned" programs > >to empty the digestive system by vomiting or diarrhea and to > >mobilize an immune mechanism to fight infection. > > > >I take the similarities between the ENS and the brain plus the > >relative independence of the ENS to be further reasons to attribute > >gastrointestinal PD symptoms to direct involvement of the ENS in > >the disease. > > > >The study of Parkinson's disease as it relates to the enteric nervous > >system is relatively new. There is some research in this area, but > >it has not yet yielded information or drugs for managing > >gastrointestinal PD symptoms. Swallowing difficulties and > >constipation in PD are handled in basically the same way as they are > >for people without PD. Sinemet, the principal PD drug, was designed > >to deliver levodopa across the brain-blood barrier to the brain, not > >to the ENS. Effects of PD drugs on the ENS are largely unknown. > > > >Hopefully more research will be done. The NIH has increased > >funding to the new field of neurogastroenterology, and the NPF has > >also provided funds. At least PD can no longer be thought of as a > >disorder eminating from the central nervous system alone. > > > > > > Bibliography > > > >Lewis, Ricki. "Neurogastroenterologists Combine Old And New > >Research Approaches." The Scientist, Vol 10, #10, pp. 13-14. May > >13, 1996. On-line at > >http://www.the-scientist.library.upenn.edu/yr1996/may/ > >research_960513.html. > > > >Quigley, Eamonn M.M. "Gastrointestinal Dysfunction in Parkinson's > >Disease." Seminars in Neurology. Vol 16, #3, pp. 245-250. > >September 1996. > > > >"Body's 'Second Brain' May Cause Digestive Disorders." The New > >York Times, Jan. 23, 1996. > >