X-ray diffraction study of fast and slow mammalian skeletal muscle in the live relaxed state.

ABSTRACT

Experimental methods have been developed by which fast and slow muscles of the mouse can be maintained in good condition for the time needed to record detailed X-ray patterns. The results presented here show that thick filaments of both types of fibre show only minor differences from those of frog muscle. However, in slow muscle alone a remarkable transformation of this structure can occur.