Editors' ChoiceCalcium signaling

Tug at the Heart Strings

Sci. Signal.  13 Sep 2011:
Vol. 4, Issue 190, pp. ec250
DOI: 10.1126/scisignal.4190ec250

When the heart fills with blood, the muscle cells relax and stretch. To find out how individual heart muscle cells, or cardiomyocytes, respond to stretching, Prosser et al. (see the Perspective by Hidalgo and Donoso) suspended single rodent cardiomyocytes between glass rods, stretched them just a little, and monitored the release of tiny amounts of calcium through channels known as ryanodine receptors. Loading the cells with fluorescent dyes sensitive to the binding of calcium or reactive oxygen species (ROS) revealed that activation of the enzyme nicotinamide adenine dinucleotide phosphate oxidase 2 triggered ROS generation, which then led to opening of the ryanodine receptor pore. Cells from animals with muscular dystrophy showed excessive calcium release, which may contribute to impaired muscle function.

B. L. Prosser, C. W. Ward, W. J. Lederer, X-ROS signaling: Rapid mechano-chemo transduction in heart. Science 333, 1440–1445 (2011). [Abstract] [Full Text]

C. Hidalgo, P. Donoso, Getting to the heart of mechanotransduction. Science 333, 1388–1390 (2011). [Abstract] [Full Text]