Mechanoenergetics of smooth muscle

All muscles in our body release heat as they produce force and perform work. We have thus developed highly sensitive calorimeters for simultaneously measuring the force production and heat release of tiny samples of heart muscle, as they repeatedly perform work against time-varying loads. Our current systems are ‘flow-through’ and routinely used to test the force (~1 mN) and heat-rate (~1 µW) production of cardiac muscle samples that are less than 0.5 mm in diameter and ~2 mm long. However, less is known about the mechanics and corresponding energetics of smooth muscle tissue. This is partly because smooth muscle tissues generally have higher efficiency than cardiac, cannot be rapidly paced, and are thus likely to produce a lower level of heat. 

In this project, we plan to develop and use a new microcalorimetric system for measuring force and heat output from smooth muscle tissue samples. The task will involve developing a new calorimeter that allows a larger volume of tissue to be studied at a much reduced flow rates; the use of a no-flow design will be investigated as a possible technique to account for the lower heat output of smooth muscle cells. As a novel alternative approach, the project will also estimate smooth muscle energetics by measuring the consumption of oxygen over time using an existing Oxygraph device, or oxygen probes, that can handle larger samples of tissue (15x5 mm). This approach would also allow the muscle geometry and movement to be directly imaged with a high-resolution camera. The incorporation of a force measurement system will represent another possible step of improvement. 

With this instrument, the student will perform mechanoenergetics measurements on tissues from smooth muscle organs (such as the gastrointestinal tract, or the uterus). These techniques and measurements will be used in the future to help investigate the effects new pharmaceutical on smooth muscle organs and to develop mathematical models of smooth muscle cell function.

A background in biomedical engineering, physics, electronics or similar discipline will be helpful. 

MiGEM

Page expires: 20 June 2025