Medicine and Health Sciences Commons^™

Muscle Fiber Size And Composition Differences Between Ames Dwarf Mice And Wild-Type Mice, Jordan Anderson

Physical Therapy Scholarly Projects

Background: Ames dwarf mice demonstrate delayed aging processes in multiple body systems. We compared muscle composition and area between dwarf and wild-type mice to determine if any significant differences exist.

Methods: We resected soleus, gastrocnemius/plantaris, tibialis anterior, and extensor digitorum longus muscles from both dwarf and wild-type mice, then froze, sliced, set on slides, and stained to isolate fast-twitch and slow-twitch fibers. Microscopy images were taken at 10x magnification and fiber composition and cross-sectional area were measured in soleus muscles.

Results: Wild-type mice had an average composition of 52.3% fast-twitch and 47.7% slow-twitch fibers while dwarf mice had 66.3% slow-twitch …

Sarcopenia And Current Research Using Ames Dwarf Mice: A Research Study, Amanda Sodemann

Physical Therapy Scholarly Projects

This research project focused on the differences observed in muscle fiber composition and surface area between wild type mice and Ames dwarf mice as they aged. A mouse model was utilized because the skeletal muscle framework of mice closely resembles that of human muscle; thus, the observations seen within the mice may also be seen within humans as they age. Comparisons between the wild type and dwarf mice include a smaller cross-sectional muscle area in a dwarf mouse and no drastic change in the percentages of fast and slow twitch muscle fibers as the dwarf mouse ages. Furthermore, differences in …