The effect of serotonergic modulation on intestinal permeability and visceral perception in healthy individuals and IBS patients

IBS-patients
Inclusion criteria:
1) IBS will be diagnosed according to the Rome III criteria*:
Recurrent abdominal pain or discomfort at least 3 days per month in the last 3 months associated with 2 or more of the following:
• Improvement with defecation
• Onset associated with a change in frequency of stool
• Onset associated with a change in form (appearance) of stool
* Criteria fulfilled for the last 3 months with symptom onset at least 6 months prior to diagnosis
* Discomfort means an uncomfortable sensation not described as pain. In pathophysiological research and clinical trails, a pain/discomfort frequency of at least 2 days a week during screening evaluation is an indication for subject*s eligibility.;2) Based on the medical history and previous examination, no other causes for the abdominal complaints can be defined.
3) Age between 18 and 65 years;Healthy individuals
Inclusion criteria:
1) Based on medical history and previous examination, no gastrointestinal complaints can be defined.
2) Age between 18 and 65 years

Exclusion criteria for IBS patients:;1) History of psychiatric disorders including use of psychoactive medication or psychological symptomatology, defined as a diagnosis on the global severity index score on SCL-90 for females >=150, for males >=131, or HADS scores >= 8. First-degree family members with psychiatric disorders
2) Inability to stop medication that can influence gastrointestinal motility or perception (like loperamide, butylscopolamine, psylliumsead (metamucil), duspatal, metoclopramide, domperidon, erytromycine), or serotonin metabolism (carbidopa, food supplementation) for at least 3 days before tests.
3) Administration of investigational drugs in the 180 days prior to the study
4) Major abdominal surgery interfering with gastrointestinal function (uncomplicated appendectomy, cholecystectomy and hysterectomy allowed, and other surgery upon judgement of the principle investigator)
5) Premenstrual syndrome, dieting (medically prescribed, vegetarian, diabetic, macrobiological, biological dynamic), pregnancy, lactation
6) Excessive alcohol consumption (>20 alcoholic consumption per week)
7) Smoking
8) Blood donation within 3 months before the study period
9) Self-admitted HIV-positive state
10) Irregular day-night rhythm;Exclusion criteria for healthy individuals:
1) History of psychiatric disorders including use of psychoactive medication or psychological symptomatology, defined as a diagnosis on the global severity index score on SCL-90 for females >=150, for males >=131, or HADS scores >= 8
First-degree family members with psychiatric disorders
2) Use of medication, except oral contraceptives, within 14 days prior to testing
3) Administration of investigational drugs in the 180 days prior to the study
4) Major abdominal surgery interfering with gastrointestinal function (uncomplicated appendectomy, laparoscopic cholecystectomy and hysterectomy allowed, and other surgery upon judgement of principle investigator)
5) Premenstrual syndrome, dieting (medically prescribed, vegetarian, diabetic, macrobiological, biological dynamic), pregnancy, lactation
6) Excessive alcohol consumption (>20 alcoholic consumption per week)
7) Smoking
8) Blood donation within 3 months before the study period
9) Self-admitted HIV-positive state
10) Irregular day-night rhythm