Biomaterial Database

A laser diffraction system with improved sensitivity for long-time measurements of sarcomere dynamics in isolated cardiac myocytes. 1988

E Niggli

Department of Physiology, University of Berne, Switzerland.

To measure the mechanical activity of enzymatically isolated mammalian myocytes the principle of laser light diffraction was used. Since the viability of isolated cardiac myocytes showed a marked dependence on the laser power used, an opto-electronic system with improved light sensitivity and low susceptibility to optical noise was developed. The high sensitivity was achieved by a novel approach in the detection of diffraction patterns, that provides a significant reduction of the amount of laser power required. This improvement rendered possible the application of laser diffraction during extended experiments including pharmacological interventions. The static performance of the system, as assessed by means of calibration gratings, showed a resolution in the order of 5 nm for small changes in sarcomere length in the range from 1.2 microns to 2.0 microns. Examples of measurements on resting and contracting cells are presented, and the limitations of the application of the system to biological specimens are discussed.

UI	MeSH Term	Description	Entries
D007834	Lasers	An optical source that emits photons in a coherent beam. Light Amplification by Stimulated Emission of Radiation (LASER) is brought about using devices that transform light of varying frequencies into a single intense, nearly nondivergent beam of monochromatic radiation. Lasers operate in the infrared, visible, ultraviolet, or X-ray regions of the spectrum.	Masers,Continuous Wave Lasers,Pulsed Lasers,Q-Switched Lasers,Continuous Wave Laser,Laser,Laser, Continuous Wave,Laser, Pulsed,Laser, Q-Switched,Lasers, Continuous Wave,Lasers, Pulsed,Lasers, Q-Switched,Maser,Pulsed Laser,Q Switched Lasers,Q-Switched Laser
D009200	Myocardial Contraction	Contractile activity of the MYOCARDIUM.	Heart Contractility,Inotropism, Cardiac,Cardiac Inotropism,Cardiac Inotropisms,Contractilities, Heart,Contractility, Heart,Contraction, Myocardial,Contractions, Myocardial,Heart Contractilities,Inotropisms, Cardiac,Myocardial Contractions
D009206	Myocardium	The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.	Muscle, Cardiac,Muscle, Heart,Cardiac Muscle,Myocardia,Cardiac Muscles,Heart Muscle,Heart Muscles,Muscles, Cardiac,Muscles, Heart
D009210	Myofibrils	The long cylindrical contractile organelles of STRIATED MUSCLE cells composed of ACTIN FILAMENTS; MYOSIN filaments; and other proteins organized in arrays of repeating units called SARCOMERES .	Myofilaments,Myofibril,Myofilament
D002469	Cell Separation	Techniques for separating distinct populations of cells.	Cell Isolation,Cell Segregation,Isolation, Cell,Cell Isolations,Cell Segregations,Cell Separations,Isolations, Cell,Segregation, Cell,Segregations, Cell,Separation, Cell,Separations, Cell
D004559	Electric Wiring	An arrangement of wires distributing electricity.	Electrical Wiring,Wiring, Electric,Wiring, Electrical
D006321	Heart	The hollow, muscular organ that maintains the circulation of the blood.	Hearts
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012518	Sarcomeres	The repeating contractile units of the MYOFIBRIL, delimited by Z bands along its length.	Sarcomere
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor