Human Intestinal Amino Acid Absorption and the Role of a Local (Renin)-Angiotensin System (RAS)

Status

Completed

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT01252368

Enrollment

Registered

2010-12-03

Start date

2009-12-31

Completion date

2011-05-31

Last updated

2012-11-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Healthy Participants, Hypertension

Brief summary

Aim of this trial is to investigate the expression and localisation of different amino acid transporters and their regulatory proteins derived from the regulatory proteins of the local renin angiotensin system (RAS) in the intestine. This is investigated on one hand in patients who do not take any drugs interfering with RAS. On the other hand expression analysis is done in patients taking daily RAS-active drugs, like ACE inhibitors or sartanes. After obtaining informed consent of patients attending the hospital for clarification of gastrointestinal symptoms by gastroduodenoscopy or colonoscopy, 2 biopsies (in addition to biopsies needed for clinical diagnostics) will be taken from each duodenum, jejunum, ileum and descending colon. Biopsies are investigated anonymously at the Institute of Physiology of the University of Zurich. The mRNA content of amino acid transporters and regulatory proteins, respectively, in the biopsies is analyzed by quantitative PCR. Transport proteins are in addition analyzed with immunohistochemistry. Furthermore amino acid concentration in plasma and urine samples are analyzed by HPLC. From plasma and serum samples RAS parameters like renin, aldosterone, ACE and angiotensin(1-7) are measured.

Interventions

BIOLOGICALhypertension

patients taking daily ACE inhibitors or sartanes

Study design

Observational model

CASE_CONTROL

Time perspective

PROSPECTIVE

Eligibility

Sex/Gender

ALL

Age

18 Years to 80 Years

Healthy volunteers

Yes

Inclusion criteria

* Men and women aged 18-80 years * BMI 18-35 kg/m2 * Group 1: patients taking daily RAS-active drugs, like ACE inhibitors or sartanes (treatment indication outside of this study) * Group 2: no therapy with RAS-active drugs, like ACE inhibitors or sartanes Gastroduodenoscopy and/or colonoscopy with a treatment indication outside of this study * Informed consent

Exclusion criteria

* Severe pathologic alterations in the gastrointestinal tract (ulcers, tumors, celiac disease; GERD and gastritis are no

Countries

Switzerland

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026