Abstract
Polyethylenglycol narrows the lattice spacing of skinned skeletal muscle sarcomere. Since the size of polyethylenglycol ( M.W. 3350 ) seems around few nanometers, the lattice spacing of around 40 nanometers was seemed to be large enough for penetration of polyethylenglycol. To reveal whether the polyethylenglycol penetrates into the sarcomere or not, I measured the specific gravity of myofibril suspensions from rabbit psoas muscle in the presence or absence of polyethylenglycol. If polyethylenglycol dose not penetrate into the sarcomere, the specific gravity of the supernatant after centrifugation of myofibril suspension is larger than the specific gravity of myofibril suspension. [J Physiol Sci. 2008;58 Suppl:S65]
