Neutron diffraction measurements of skeletal muscle using the contrast variation technique; Analysis of the equatorial diffraction patterns

Fujiwara, Satoru; Takezawa, Yasunori*; Sugimoto, Yasunobu*; Wakabayashi, Katsuzo*

In neutron scattering and diffraction, information on variations of scattering length density of molecules of interest can be extracted by the contrast variation technique. In order to explore the possibilities of this contrast variation technique in neutron fiber diffraction, neutron diffraction measurements of skeletal muscles were performed. The neutron fiber diffraction patterns of frog sartorius muscles were measured in the relaxed state and the rigor state, in various DO concentrations. It was shown that there were variations in the scattering length density of the protein regions in the unit cell of the muscle structure. Analysis of the equatorial reflections showed that the phase information of these reflections is obtained, that the scattering length density is different between the thick filament region and the thin filament region, and that the density of the thick filament changes as the state of muscle changes from the relaxed state to the rigor state.