myostatin
noun
myo·stat·in
| \ ˌmī-ə-ˈsta-tᵊn
\
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Medical Definition of myostatin
: a protein found mainly in skeletal muscle that is a transforming growth factor acting to restrain the growth of muscles
Two treatments that block a protein called myostatin, which slows muscle growth, are now in the pipeline.— Rowan Hooper, New Scientist, 10 Dec. 2005