SLOW AND MACROSCOPIC MODULATION OF THERMAL FLUCTUATIONS IN MYOFIBRILS

A comparison was made between fluctuations in a length of sarcomere fr om a myofibril during relaxed and rigor conditions. The fluctuations o f the length associated with rigor states was due entirely to thermal fluctuations in the ambient. In contrast, the fluctuations associated with relaxed states were accompanied by extremely slow and macroscopic ally modulated thermal fluctuations. A slow, macroscopic modulation of the thermal fluctuations of the length of sarcomere was found to be u nique to myofibrils in their relaxed conditions.