Compensatory muscular hypertrophy in the extensor digitorum longus muscle of the mouse

Hypertrophy of the extensor digitorum longus muscle after surgical removal of its companion tibialis anterior muscle has been studied in mice. Early, intermediate and late stages in the process of hypertrophy have been defined. The proportional increase in the man cross sectional area of fibres in a hypertrophic muscle consistently exceeded the proportional increase in the weight of the same muscle in all animals. This suggests that hypoplasis (loss of fibres) was occurring. This work was carried out with the aid of grants from the Medical Research Council and Science Research Council of Great Britain.