Transverse tubule remodeling enhances Orai1-dependent Ca²⁺ entry in skeletal muscle.

ABSTRACT: Exercise promotes the formation of intracellular junctions in skeletal muscle between stacks of sarcoplasmic reticulum (SR) cisternae and extensions of transverse-tubules (TT) that increase co-localization of proteins required for store-operated Ca²⁺ entry (SOCE). Here, we report that SOCE, peak Ca²⁺ transient amplitude and muscle force production during repetitive stimulation are increased after exercise in parallel with the time course of TT association with SR-stacks. Unexpectedly, exercise also activated constitutive Ca²⁺ entry coincident with a modest decrease in total releasable Ca²⁺ store content. Importantly, this decrease in releasable Ca²⁺ store content observed after exercise was reversed by repetitive high-frequency stimula

SUBMITTER: Michelucci A 

PROVIDER: S-EPMC6837846 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature