Mitosis-to-G1 phase transition of HTC cells obtained with nocodazole (R 17934; NSC 238159): Spin-lattice relaxation time and cytofluorometric analysis

Analysis of spin-lattice relaxation time (2-r) of water protons in synchronized populations of Hela cells shows that the motional freedom of cellular water is maximum during mitosis (M), then decreases very rapidly during Gl to reach a minimum in the DNA synthetic phase S [I]. The progressive increase in water microvisco~ty during the M-G 1 transition has been attributed to an increase in chromatin diffusiveness [ 1,2]. This work aims at determining whether variation of T, observed during the M-Cl transition of synchronized populations of Hela cells can be detected in other systems.