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Effect of nitric oxide on single skeletal muscle fibres from the mouse
Author(s) -
Andrade Francisco H.,
Reid Michael B.,
Allen David G.,
Westerblad Håkan
Publication year - 1998
Publication title -
the journal of physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.802
H-Index - 240
eISSN - 1469-7793
pISSN - 0022-3751
DOI - 10.1111/j.1469-7793.1998.577bn.x
Subject(s) - nitric oxide , myofibril , chemistry , sodium nitroprusside , biophysics , skeletal muscle , medicine , snap , endocrinology , biochemistry , biology , computer graphics (images) , organic chemistry , computer science
1 Single skeletal muscle fibres from a mouse foot muscle were used to investigate the effects of nitric oxide on contractile function. 2 We measured force production and myoplasmic free Ca 2+ concentration ([Ca 2+ ] i ) in single fibres exposed to the nitric oxide donors S ‐nitroso‐ N ‐acetylcysteine (SNAC) and nitroprusside. 3 The nitric oxide donors reduced myofibrillar Ca 2+ sensitivity, whereas [Ca 2+ ] i transients were increased during submaximal tetani. Force was largely unchanged. SNAC did not change maximum shortening velocity, the rate of force redevelopment, or force production at saturating [Ca 2+ ] i . 4 The guanylyl cyclase inhibitor LY83583 increased tetanic [Ca 2+ ] i but had no effect on Ca 2+ sensitivity. LY83583 did not prevent the decrease in myofibrillar Ca 2+ sensitivity in response to SNAC. The oxidizer sodium nitrite increased tetanic [Ca 2+ ] i and decreased myofibrillar Ca 2+ sensitivity. 5 We conclude that under our experimental conditions nitric oxide impairs Ca 2+ activation of the actin filaments which results in decreased myofibrillar Ca 2+ sensitivity.