Hi SjanaJayne, serotonin has a lot to do with IBS, but at the gut level its very important to IBS specifically. 95 percent of it is found in the gut and it is a mediator also to the brain as a neurotransmitter.There is a lot of information on all this and it would take me a little time to post it all so I will post a little at a time for you, I will post more tomorrow for you also.This is new and at the gut level. Its important because it initiates peristalsis. Its also important in the singals it sends to the brain and back.When you eat, "the act of eating" releases it at the gut level to start contractions. However, other factors can influnece its release as well."PathophysiologyAltered Serotonin Signaling?The pathogenesis of IBS remains obscure, and in particular, an explanation for alternating diarrhea and constipation has been elusive. In arguably one of the most important papers presented during this year's meeting, Moses and colleagues 21 studied potential deregulation of the gut's serotonin transporter in IBS.It is known that serotonin 5-hydroxytryptamine or 5HT is released from enteroendocrine or enterochromaffin cells in response to either chemical or mechanical stimulation of the gut mucosa. Serotonin in turn initiates peristalsis, and then the serotonin released is taken up in health by a highly selective serotonin transporter SERT. One potential mechanism that could explain altered bowel function in IBS is an abnormality in the serotonin transporter itself. The study authors evaluated this hypothesis in patients with IBS with constipation and IBS with diarrhea compared with patients with ulcerative colitis and healthy controls. They were able to convincing show on blinded review that SERT immunoreactivity was less intense in patients with IBS with constipation and patients with ulcerative colitis.If these findings are indeed correct, they represent a landmark observation. The findings suggest that patients with constipation and IBS may have a reduced capacity to reuptake serotonin, leading to excess free serotonin and then desensitization of these receptors, thus reducing motor function. In contrast, in the setting of diarrhea, serotonin uptake was normal. If the underlying abnormality in serotonin transporter function alternated, then this would in turn explain alternating constipation and diarrhea.These data strongly suggest that IBS is a "real" gut disease and a potential diagnostic disease marker. They also suggest that it is valid to subdivide IBS into constipation and diarrhea symptom subgroups. This study also provides additional rationale for the use of serotonin-modulating agents in IBS and provides a new target for drug modulation. Confirmation of these very exciting initial findings in larger patient samples is awaited with great interest."
http://www.medscape.com/viewarticle/444514 Although this is a question on taking a 5ht supplement, which does not to a lot for IBS and I will explain why if you want me to, but does offer a good desription of the gut mechanisms.Harvard" Ask The Expert.General Medical Questions.Q: I have suffered from irritable-bowel syndrome for many years. I get diarrhea. The doctors I've seen have offered little help. Recently, my daughter suggested I try an over-the-counter medicine called "5-Hydroxy-tryptophan," made by a company called Natrol Inc. My daughter says it is a mild antidepressant. It seems to have helped quite a bit, but it also seems to slow me down and make me feel tired. Can you give me any information on this? What is it, exactly, and are there any serious side effects? The only other medicine I take is Synthroid....The Trusted Source..Harold J. DeMonaco, M.S.Harold J. DeMonaco, M.S., is senior analyst, Innovative Diagnostics and Therapeutics, and the chair of the Human Research Committee at the Massachusetts General Hospital. He is author of over 20 publications in the pharmacy and medical literature and routinely reviews manuscript submissions for eight medical journals...June 19, 2001.A:Irritable bowel syndrome is now recognized as a disorder of serotonin activity. Serotonin is a neurotransmitter in the brain that regulates sleep, mood depression, anxiety, aggression, appetite, temperature, sexual behavior and pain sensation. Serotonin also acts as a neurotransmitter in the gastrointestinal tract.Excessive serotonin activity in the gastrointestinal system enteric nervous system is thought to cause the diarrhea of irritable-bowel syndrome. The enteric nervous system detects bowel distension expansion on the basis of pressure-sensitive cells in the bowel lumen opening. Once activated, these pressure-sensitive cells promote the release of serotonin, which in turn promotes both secretory function and peristaltic function the contractions of the intestines that force the contents outward. At least four serotonergic receptors have been identified to be participants in the secretory and peristaltic response.Patients with diarrhea-predominant IBS may have higher levels of serotonin after eating than do people without the disorder. This recognition led to the development of the first drug used specifically to treat diarrheal symptoms of IBS, alosetron also known as Lotronex. Alosetron blocked the specific serotonin receptors responsible for recognizing bowel distention. In doing so, it blocked the effects of serotonin and reduced both bowel secretions and peristalsis. Constipation was the most common side effect seen. Note: Alosetron was removed from the market by the manufacturer after repeated reports of a dangerous condition known as ischemic colitis became known. Tegaserod Zelmac is another drug under development and under review by the U.S. Food and Drug Administration for approval. Tegaserod is indicated for the treatment of constipation-predominant IBS and works to increase enteric nervous system serotonin activity.So, increasing serotonin activity in the enteric nervous system produces increased bowel secretions and peristalsis and potentially diarrhea, whereas depressing serotonin activity produces reduced secretions and reduce peristalsis and potentially constipation. Increasing serotonin activity in the brain would increase awareness and, in higher doses, produce anxiety, insomnia and restlessness. So I would have expected exactly the opposite effects of those that you experienced.I am unable to identify any possible drug interactions between 5-HTP and Synthroid levothyroxine but the symptoms described suggest a check with your doctor may be in order. Persistent feelings of tiredness and constipation may be signs of an underactive thyroid hypothyroidism.June 19, 2001This is also important to read on all this for the information on the brain in the gut and the connections to the brain.
http://www.ibsgroup.org/other/usnews000403.htm This is a recent study on women with it after eating, basically the act of eating and the release of it from specific cells at the gut level.Levels of 5-Hydroxytryptamine Increase After Meals in Women With Irritable Bowel SyndromeNEW YORK Reuters Health May 05 - Platelet-depleted plasma 5-hydroxytryptamine 5-HT levels increase after meals in women with diarrhea-predominant irritable bowel syndrome d-IBS whose symptoms increase following food ingestion, according to a report in the May issue of Gut.In small studies, 5-HT concentrations in platelet-poor plasma appear higher in women with d-IBS than in healthy women, the authors explain, suggesting a possible link between 5-HT and postprandial symptom exacerbations or IBS itself.Dr. L. A. Houghton from University Hospital of South Manchester, UK and colleagues assessed 5-HT and 5-HIAA its metabolite concentrations, 5-HT turnover, and platelet 5-HT stores in 39 women with d-IBS and 20 healthy female volunteers before and after a standard carbohydrate meal.Although there was no difference in the ratio of postprandial to fasting 5-HT levels between d-IBS patients and healthy controls, the authors report, d-IBS subjects did have higher postprandial concentrations of 5-HT with earlier peak 5-HT levels than did healthy women.Women with d-IBS who reported symptoms following the meal also tended to have higher 5-HT concentrations and higher peak concentrations than did other women, the report indicates, though there was no difference in the time to peak levels compared with asymptomatic women with d-IBS.Fasting 5-HIAA levels were higher in d-IBS women than in healthy controls, the researchers note, but postprandial concentrations did not differ.Fasting and postprandial 5-HT turnover the ratio of 5-HIAA to 5-HT levels did not differ between healthy controls and women with d-IBS, the results indicate, but d-IBS subjects with postprandial symptoms tended to have a lower 5-HT turnover than did d-IBS women without symptoms.Women with d-IBS had significantly higher platelet 5-HT stores than did healthy women, the investigators find, though levels did not differ between d-IBS patients with and without postprandial symptoms."Our results have shown for the first time that symptom exacerbation following meal ingestion in female subjects with d-IBS is associated with increased levels of plasma 5-HT, together with a reduction in 5-HT turnover," the authors conclude. "In addition, baseline platelet stores of 5-HT are elevated in female subjects with d-IBS compared with healthy subjects, supporting increased exposure of platelets to 5-HT in the systemic circulation.""Platelet 5-HT concentrations may have a potential role to play as a marker in the diagnosis and management of d-IBS," the researchers suggest. "This would be similar to the way glycosylated hemoglobin is used to reflect mean blood glucose concentration over a prolonged time period in patients with diabetes mellitus."The investigators add, "Further studies addressing both mucosal 5-HT concentrations and enteroendocrine cell numbers in subjects with d-IBS, as well as similar studies to the present one conducted in subjects with constipation predominant IBS and assessing the transient relationship between symptoms and the 5-HT system need to be performed."Gut 2003;52:663-670.Hope this helps some, there is mmore and there are other parts to this picture that are really important and I will post some more for you, but its a good start.
