Preparation of Drosophila Heart: A Technique to Study Heart Physiology in the Adult Fly

- Different than in vertebrates, the Drosophila heart is part of an open circulatory system. The heart of an adult fly is a tube-like structure built from cardiomyocytes that is connected to the epidermis by alary muscles and embedded in extracellular matrix. The heart chamber is on the posterior end of the fly and pumps hemolymph into the aorta from which it flows into the open body cavity.

In insects, the hemolymph serves as both blood and interstitial fluid, carrying nutrients, signaling molecules, and immune cells. Additional landmarks of the heart include ostia, which are openings along the tube, and intracardiac valves. Pericardial cells are localized along the heart tube and are part of the fly's excretory system.

In an experimental heart preparation, the artificial hemolymph mimics physiological conditions to preserve tissue function. Although natural hemolymph is not responsible for gas exchange, the artificial hemolymph must be well oxygenated to substitute for the lack of a functional tracheal system. In the following experiment, we demonstrate a semi-intact heart preparation from an adult fly for live imaging or electrophysiology.

- Before getting started, we first prep