Mitochondria Are Fast Ca Sinks in Rat Extraocular Muscles: A Novel Regulatory Influence on Contractile Function and Metabolism
نویسندگان
چکیده
PURPOSE. The ultrafast extraocular muscles necessitate tight regulation of free cytosolic Ca concentration ([Ca ]i). Mitochondrial Ca influx may be fast enough for this role. In the present study, three hypotheses were tested: (1) Mitochondrial Ca uptake regulates [Ca ]i and production of force in extraocular muscle; (2) mitochondrial content correlates with their use as Ca sinks; and (3) mitochondrial content in extraocular muscle is determined by the transcription factors and coactivators that initiate muscle adaptation to aerobic exercise.
منابع مشابه
Mitochondria are fast Ca2+ sinks in rat extraocular muscles: a novel regulatory influence on contractile function and metabolism.
PURPOSE The ultrafast extraocular muscles necessitate tight regulation of free cytosolic Ca2+ concentration ([Ca2+]i). Mitochondrial Ca2+ influx may be fast enough for this role. In the present study, three hypotheses were tested: (1) Mitochondrial Ca2+ uptake regulates [Ca2+]i and production of force in extraocular muscle; (2) mitochondrial content correlates with their use as Ca2+ sinks; and ...
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