The spin-lattice relaxation times of water associated with early post mortem changes in skeletal muscle.

We studied the spin-echo signal of muscle water in a large time domain and found that the motion of the nuclear magnetic moment of tissue water cannot be characterized by a single spin-lattice relaxation time (T1). The relaxation time T1B, which is the T1 characterized by those protons with a slower relaxation rate, is influenced by the early post mortem changes in skeletal muscle. T1B increased with time after the tissue was taken from the animal and reached a maximum at 3 h. However, the weighted average of T1 of all water protons (T1A) did not change throughout the time course of the experiments.