Study of Intraduodenal Calcium Infusion Effects on Blood Sugar, Hormones, and Stomach Emptying in Men with Type 2 Diabetes

What this Trial Is About

Researchers are evaluating the effects of calcium on gut function and blood sugar control in men with type 2 diabetes. The study aims to understand how intraduodenal infusion of calcium chloride at different doses influences plasma glucose levels, gut hormones, gastric emptying, and gastrointestinal symptoms. This research is conducted by the University of Adelaide and involves a randomized, triple-blind study design. Participants will receive three separate 75-minute infusions through a catheter placed into the duodenum. The infusions include saline control, 500 mg calcium chloride, or 1000 mg calcium chloride, given in random order over sessions spaced at least 4 days apart. Each session lasts 4 to 6 hours and includes careful monitoring with blood sampling, breath tests, and symptom questionnaires. During each visit, participants will fast overnight and consume a standardized meal before arrival. Blood pressure, heart rate, and temperature are checked, and an intravenous line is placed for blood sampling. Blood and breath samples will be collected at multiple times before and after ingestion of a mixed-nutrient drink to measure glucose, hormones, and gastric emptying. Gastrointestinal symptoms will be assessed using questionnaires. After the final collection, participants receive a light lunch and leave. Total blood drawn per participant during the study is about 310 mL including screening.

Effects of Calcium on Gut Functions and Blood Glucose in Humans With Type 2 Diabetes