Fast Measurement of Sarcomere Length and Cell Orientation in Langendorff-Perfused Hearts Using Remote Focusing Microscopy

Fast measurement of sarcomere length and cell orientation in Langendorff-perfused hearts using remote focusing microscopy.

RATIONALE Sarcomere length (SL) is a key indicator of cardiac mechanical function, but current imaging technologies are limited in their ability to unambiguously measure and characterize SL at the cell level in intact, living tissue. OBJECTIVE We developed a method for measuring SL and regional cell orientation using remote focusing microscopy, an emerging imaging modality that can capture li...

NEW METHODS IN CARDIOVASCULAR BIOLOGY Fast Measurement of Sarcomere Length and Cell Orientation in Langendorff-Perfused Hearts Using Remote Focusing Microscopy

Optical mapping of Langendorff-perfused rat hearts.

Optical mapping of the cardiac surface with voltage-sensitive fluorescent dyes has become an important tool to investigate electrical excitation in experimental models that range in scale from cell cultures to whole-organs([1, 2]). Using state-of-the-art optical imaging systems, generation and propagation of action potentials during normal cardiac rhythm or throughout initiation and maintenance...

Regional ischemia in hypertrophic Langendorff-perfused rat hearts.

Myocardial hypertrophy decreases the muscle mass-to-vascularization ratio, thereby changing myocardial perfusion. The effect of these changes on myocardial oxygenation in hypertrophic Langendorff-perfused rat hearts was measured using epimyocardial NADH videofluorimetry, whereby ischemic myocardium displays a high fluorescence intensity. Hypertrophic hearts, in contrast to control hearts, devel...

Voltage-sensitive dye mapping in Langendorff-perfused rat hearts.

An imaging system suitable for recordings from Langendorff-perfused rat hearts using the voltage-sensitive dye 4-[beta-[2-(di-n-butylamino)-6-naphthyl]vinyl]pyridinium (di-4-ANEPPS) has been developed. Conduction velocity was measured under hyper- and hypokalemic conditions, as well as at physiological and reduced temperature. Elevation of extracellular [K(+)] to 9 mM from 5.9 mM caused a slowi...