GastroFlow: Investigation of the Gastrointestinal Blood Flow in Patients With Postprandial Hypotension (Gastroflow)

This project will describe the mechanisms of action and the relative contributions of GIP to changes in gastrointestinal blood flow induced by oral glucose and endogenous GIP with the use of a receptor antagonists GIP(3-30)NH2 in patients with postprandial hypotension.

Study Overview

• Status: Enrolling by invitation
• Conditions: Healthy; Blood Flow; Postprandial Hypotension
• Intervention / Treatment: Other: MRI + GIPR antagonist (Tool); Other: MRI + hangrip; Other: Saline and oral glucose

Detailed Description

Each participant will attend three independent randomised experimental days in the MRI-scanner with intravenous infusion (hormone/placebo) and oral ingestion (glucose): An intravenous infusion of saline or GIP(3-30)NH2 starts at time point -20 minutes.The infusions are combined with an oral glucose tolerance test (75 gram of glucose dissolved in 250 ml water ingested orally) at time point 0 minutes on two of the experimental days (with and without GIP(3-30)NH2). Furthermore one day will be with handgrip exercise, without an infusion. Therefore the first two days are in randomized order.

MRI measurements are repeatedly performed and blood samples are drawn to be analysed for endocrine responses from the intestines and pancreas.

• Study Type: Interventional
• Enrollment (Estimated): 30
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Denmark
  • Glostrup Municipality, Denmark, 2600
    • Glostrup Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

For the PPH group

Inclusion Criteria:

• Postprandial hypotension
• Symptoms of postprandial hypotension

Exclusion Criteria:

• Treatment with drugs that cannot be paused for 12 hours
• Metallic implants that does not tolerate MRI
• Any other disease or dysfunction that may disturb blood flow to the gut
• Intake of more than 14 units of alcohol per week or abuse of drugs
• Blood vessels that are not feasible for measuring flow in the MRI scanner
• Low blood percent
• Decreased kidney function
• Decreased liver function
• Claustrophobia

For the healthy group

Inclusion Criteria:

• Matched by age, gender and BMI

Exclusion Criteria:

• Postprandial hypotension
• Metallic implants that does not tolerate MRI
• Intake of more than 14 units of alcohol per week or abuse of drugs
• Blood vessels that are not feasible for measuring flow in the MRI scanner
• Low blood percent
• Decreased kidney function
• Decreased liver function
• Claustrophobia
• Autonomic dysfunction or other disease that cause changes in blood pressure during or after a meal
• Intake of pharmaceutical products that influence the blood pressure

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Postprandial hypotension group; MRI scans of PPH patients. 3 interventions	Other: MRI + GIPR antagonist (Tool); GIP(3-30)NH2 infusion, oral glucose during MRI scans; Other: MRI + hangrip; Hangrip exercises, oral glucose during MRI scans; Other: Saline and oral glucose; Saline infusion oral glucose during MRI scans
Placebo Comparator: Healthy matched controls; MRI scans of healthy controls. Crossover design three interventions.	Other: MRI + GIPR antagonist (Tool); GIP(3-30)NH2 infusion, oral glucose during MRI scans; Other: MRI + hangrip; Hangrip exercises, oral glucose during MRI scans; Other: Saline and oral glucose; Saline infusion oral glucose during MRI scans

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Blood flow	Redistribution of splanchnic blood flow in the vessel mesenteric superior artery. Measured with functional MRI in ml/min	145 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Blood flow	Blood flow in vena portae	145 minutes
Blood flow	Blood flow in trunks coeliacus	145 minutes

Collaborators and Investigators

• Sponsor: University of Copenhagen
• Collaborators: Rigshospitalet, Denmark

Study record dates

Study Major Dates

• Study Start (Actual): September 15, 2025
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): May 1, 2027

Study Registration Dates

• First Submitted: September 3, 2025
• First Submitted That Met QC Criteria: January 27, 2026
• First Posted (Actual): February 2, 2026

Study Record Updates

• Last Update Posted (Actual): February 2, 2026
• Last Update Submitted That Met QC Criteria: January 27, 2026
• Last Verified: September 1, 2025

More Information

Terms related to this study

• Keywords: Blood flow; GIP; Physiology; Mesenteric blood flow; Postprandial hypotension; Splanchnic blood flow
• Additional Relevant MeSH Terms: Investigative Techniques; Carbohydrates; Inorganic Chemicals; Chlorine Compounds; Chemistry Techniques, Analytical; Spectrum Analysis; Sugars; Sodium Compounds; Hexoses; Monosaccharides; Chlorides; Hydrochloric Acid; Magnetic Resonance Spectroscopy; Glucose; Equipment and Supplies; Sodium Chloride
• Other Study ID Numbers: H-25007666; NNF23OC0082437 (Other Grant/Funding Number: Novo Nordisk Foundation)

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No