Biophysical properties of the muscular and vascular components of the heart are often studied in isolated cell preparations, however, it is widely appreciated that important cellular properties critically depend on interactions at the tissue and organ level, and vice versa. In cardiac muscle, membrane potential and intracellular ion concentrations are modulated by electrical properties of neighbouring cells as well as the macroscopic activation sequence of the myocardial syncytium. A myocyte's sarcomere length (SL), which is a key determinant of its energy use and contractility, is largely governed by forces imposed by the architecture of the surrounding tissue, while SL in turn impacts overall cardiac contractility (Frank-Starling mechanism). Similarly, the ability of the micro-circulation to dynamically adapt regional blood flow to the metabolic needs of the tissue critically depends on cross communication between cellular components of the vessel wall (e.g., endothelial and smooth muscle cells, autonomic nerves) as well as between vascular cells and the surrounding non-vascular cells. Thus, a better understanding of the properties of myocytes and vascular cells while still in their natural habitat is warranted. More recent advances in optical microscopy and tracer technology have improved our ability to probe cellular function and structure within the intact, living heart. Significant challenges remain, as measurements depend on the optical characteristics of the microscope and tissue, speed of acquisition, excitation wavelength and dye choices, as well as the ability of the experimenter to account for tissue motion. In addition, researchers need to consider geometrical distortions caused by tissue orientation when interpreting results.
This research topic issue focuses on recent advances in microscopic imaging of the physical structure and functional properties of muscle cells in the intact heart and vascular systems. Basic research studies, methodologic perspectives, and reviews can address both the technical aspects of measurements within intact heart and vessels and interpretation of results in light of the existing literature on isolated cells and tissues.
Biophysical properties of the muscular and vascular components of the heart are often studied in isolated cell preparations, however, it is widely appreciated that important cellular properties critically depend on interactions at the tissue and organ level, and vice versa. In cardiac muscle, membrane potential and intracellular ion concentrations are modulated by electrical properties of neighbouring cells as well as the macroscopic activation sequence of the myocardial syncytium. A myocyte's sarcomere length (SL), which is a key determinant of its energy use and contractility, is largely governed by forces imposed by the architecture of the surrounding tissue, while SL in turn impacts overall cardiac contractility (Frank-Starling mechanism). Similarly, the ability of the micro-circulation to dynamically adapt regional blood flow to the metabolic needs of the tissue critically depends on cross communication between cellular components of the vessel wall (e.g., endothelial and smooth muscle cells, autonomic nerves) as well as between vascular cells and the surrounding non-vascular cells. Thus, a better understanding of the properties of myocytes and vascular cells while still in their natural habitat is warranted. More recent advances in optical microscopy and tracer technology have improved our ability to probe cellular function and structure within the intact, living heart. Significant challenges remain, as measurements depend on the optical characteristics of the microscope and tissue, speed of acquisition, excitation wavelength and dye choices, as well as the ability of the experimenter to account for tissue motion. In addition, researchers need to consider geometrical distortions caused by tissue orientation when interpreting results.
This research topic issue focuses on recent advances in microscopic imaging of the physical structure and functional properties of muscle cells in the intact heart and vascular systems. Basic research studies, methodologic perspectives, and reviews can address both the technical aspects of measurements within intact heart and vessels and interpretation of results in light of the existing literature on isolated cells and tissues.