Studies of the T1 and T2 of intracellular water as a function of frequency in normal and transformed fetal cells.

Frequency-dependent values of the spin-lattice relaxation time (T1) and the spin-spin relaxation time (T2) have been obtained for intracellular water in normal and transformed Syrian hamster fetal fibroblasts. Values of T1 and T2 were obtained for normal and transformed cells at 24.3 (0.57 T), 100 (2.4 T), 300 (7.0 T), and 400 MHz (9.4 T). At each frequency, values of T1 were the same for both normal and transformed cells, whereas values of T2 were lower for one passage of transformed cells. As expected, T1 increased with frequency. However, T2 decreased with frequency for both normal and transformed cells. The frequency dependence of T2, was similar for all cells; thus, the ability of T2 to make a distinction between normal and transformed cells did not change with field.