Healthy
Conditions
Keywords
Gastrointestinal physiology, MRI, Small bowel water volumes, Gastric volumes
Brief summary
The GI MRI Research group at the University of Nottingham has been developing new, non-invasive magnetic resonance imaging (MRI) techniques to image the gastrointestinal tract. The investigators now want to characterise; in collaboration with the College of Pharmacy at the University of Michigan, the fasting volumes of gastric and small bowel liquid and their time courses over 2 hours after drinking the FDA recommended 240 mL of water drink for oral solid dosage forms testing.
Detailed description
Solid oral delivery is the most frequently used route of administration for pharmaceutical drug products. Along with other important physiological parameters, the volume of liquid in the small intestine (SILV) has the potential to greatly influence the rate and extent of drug dissolution and absorption in the GI tract, or oral bioperformance. Modeled small bowel absorption of a drug can vary by more than five-fold as SILV decreases from 500 to 50 ml. To obtain reasonable predictions of oral bioperformance scientists must design meaningful in vitro dissolution tests and mechanistic drug transport models that capture the range of SILV in humans. However, little is known about liquid volumes in the gut, mostly due to invasiveness of previous techniques. A recent study has drawn great attention to the possibility of the liquid in the small intestine existing in discrete liquid pockets hence it would also be desirable to monitor the time courses and volumes of individual water pockets in the small intestine. Magnetic resonance imaging (MRI) is the ideal tool to carry out serial and non-invasive imaging of gastrointestinal function. MRI is inherently suited to image liquid materials and this ability has been exploited to image liquids in the undisturbed gastrointestinal tract. Gastric emptying measurements have been long established and validated. Small bowel liquid volumes measurements have been recently validated against naso-duodenal infusion. Ultimately, the findings with this study will provide novel insights on the volume and distribution of ingested liquids in the gastrointestinal tract.
Interventions
OTHERSpring water
Sponsors
University of Michigan
University of Nottingham
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 55 Years
Healthy volunteers
Yes
Inclusion criteria
* Apparently healthy; no medical conditions that might affect the study measurements * Male or female * Age between 18 and 55 years of age * Body mass index (BMI) between 18.5 and 24.9 kg m-2 * Suitable for MRI scanning (eg absence of metal implants, infusion pumps and pacemakers as assessed by the MRI safety questionnaire
Exclusion criteria
* Previous gastrointestinal surgery (excluding cholecystectomy and appendectomy) * Known gastrointestinal disease * Smoking * History of alcohol or drug abuse * Taking medication that is likely to affect gastrointestinal function * Participation in night shift work the week prior to the study day. (Night work is defined as working between midnight and 6 am) * Strenuous exercise greater than 10 hours per week * Consumption of more than 21 units of alcohol in a typical week
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Time course of small bowel liquid volume after ingesting 240 mL of water | 0 - 120 mins | Time course for the volume of freely mobile water in the small bowel over 2 hours |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Time course of gastric liquid volume after ingesting 240 mL of water | 0 - 120 mins | Gastric volumes obtained from MRI as a function of time |
| Number of liquid pockets in the small bowel | 0 - 120 mins | Assessment of the number of pockets of liquid in the small bowel as seen on the MR images |
| Volume of liquid pockets in the small bowel | 0 - 120 mins | The volume of freely mobile liquid in each of the liquid pockets identified on the MR image |
| Summary information on the location of liquid pockets by quadrant | 0 - 120 mins | Details on the distribution of the liquid pockets as seen on the MR images |
Countries
United Kingdom
Outcome results
None listed