Lying between single cell and whole heart experimental studies, intact papillary muscle isolated from hearts offers unique advantages.
Unlike single isolated myocytes, which represent the smallest fully functional model system, intact papillary muscle can be used to study cardiac function within a multicellular context and an intact 3-dimensional myofilament lattice. And unlike whole heart studies, the contractile characteristics of papillary muscle can be evaluated independently of extrinsic factors such as vascular tone. Papillary muscle also allows measurements too difficult or impossible to perform in whole hearts. Similarly, unlike skinned preparations, intact muscle preparations allow for simultaneous detection of force production and intracellular calcium dynamics.
The new IonOptix Papillary Muscle Chamber has been designed to facilitate these measurements. Intact ventricular papillary muscle can be easily attached between a robust force transducer and programmable length controller. Chamber fluid flow allows for temperature control and continuous oxygenation of tissue, while the specialized force transducer allows for electrical excitation directly through the muscle preparation. Simple platinum “Omega” clips are tied to the muscle ends which then slip onto platinum hooks. The platinum allows for electrical conductance and are inert, therefore there is no electrolysis or disruption of biology.
Intact Muscle Chamber with force transducer and piezoelectric length controller
Combined with an IonOptix Calcium and Contractility System, fluorescence of calcium-sensitive dyes, such as Fluo-4, Fura-2 and/or Indo-1, can be detected using IonWizard, which permits control of experiment acquisition parameters and analysis of data. Whole skeletal muscle, such as mouse soleus, can be easily examined as well.
As with all of our systems, we stand behind our products. When we install our complete systems we use your preparations to help get you started as quickly as possible. And when you need assistance we offer unlimited phone and email support for the lifetime of your system.
Most of the acquisition in the muscle system is achieved through the core IonWizard software, in which trace recordings display force data and length controller position. Add the software module PMTAcq for fluorescence recording and the Advanced Signal Generator for precise muscle length control with programmable protocols.