Related Experiment Video
Updated: Jan 26, 2026

Sleeve Gastrectomy in Mice using Surgical Clips
Published on: November 14, 2020
Sleeve Gastrectomy in Obese Zucker Rats Restores Cardiac Function and Geometry Toward a Lean Phenotype Independent of
Tammy L Kindel1, Tom Foster1, Leanne Harmann2
1Departments of Surgery, Medical College of Wisconsin, Milwaukee, Wisconsin 53226.
Objective:
Bariatric surgery, including sleeve gastrectomy (SG), significantly improves cardiac geometry and function in patients with heart failure. In this study, we used the obese Zucker rat as an animal model of heart failure with preserved ejection fraction (HFpEF) to test the hypothesis that a SG will improve cardiac function independent of weight loss.
Methods And Results:
Obese, male Zucker rats underwent SG, pair-fed sham, or ad-lib sham surgery. Lean Zucker rats also underwent ad-lib sham surgery. Echocardiograms were performed preoperatively and at 6 weeks postoperatively. Obese SG and obese pair-fed sham rats had similar body weights postoperatively. Obese SG and lean, ad-lib, sham rats had a significant increase in postoperative stroke volume, and left ventricular internal diameter in diastole and systole. SG preserved systolic function and significantly improved isovolumetric relaxation time (13.9 ± 2.4 to 11.1 ± 2.1 ms, P = .02) independent of weight loss.
Discussion:
SG has a beneficial impact on both systolic and diastolic cardiac function in obese Zucker rats toward a lean phenotype independent of weight loss and caloric restriction. These findings may represent a weight-loss independent mechanism generated from the gastrointestinal tract that has the potential to improve diastolic dysfunction independent of obesity status and translate to patients with HFpEF.
Related Concept Videos
Coordination Number and Geometry
Predicting Molecular Geometry
Loss of Tumor Suppressor Gene Functions
When the tumor suppressor genes develop mutations or are lost, cells start growing out of control, leading to cancer. However, a single functional copy of the tumor suppressor gene is enough for the cells to maintain their normal functions and cell...
Restorative Care
Obesity
Introduction to Test of Independence
The test statistic for a test of independence is similar to that of a goodness-of-fit test:

