Size and Proportions of Slow-Twitch and Fast-Twitch Muscle Fibers in Human Costal Diaphragm

Figure 1

Phenotyping of muscle fibers by the expression of slow and fast MyHCs in costal diaphragm and vastus lateralis muscle. Fibers labeled by dots are slow-twitch fibers, fibers labeled by open circles are fast-twitch fibers, and hybrid fibers are labeled by arrows. Muscle fibers not stained by antibodies to slow MyHC are stained heavily or intermediately by antibodies to fast MyHC. Bar = 50 μm.