Beat-by-Beat Cardiomyocyte T-Tubule Deformation Drives Tubular Content Exchange.

ABSTRACT:

Rationale

The sarcolemma of cardiomyocytes contains many proteins that are essential for electromechanical function in general, and excitation-contraction coupling in particular. The distribution of these proteins is nonuniform between the bulk sarcolemmal surface and membrane invaginations known as transverse tubules (TT). TT form an intricate network of fluid-filled conduits that support electromechanical synchronicity within cardiomyocytes. Although continuous with the extracellular space, the narrow lumen and the tortuous structure of TT can form domains of restricted diffusion. As a result of unequal ion fluxes across cell surface and TT membranes, limited diffusion may generate ion gradients within TT, especially deep within the TT network and at high pacing rates.

Objecti

SUBMITTER: Rog-Zielinska EA 

PROVIDER: S-EPMC7834912 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature