Evidence for a significant role of paramagnetic ions in the observed NMR relaxation rates of living tissues.
نویسنده
چکیده
From the earliest days of nuclear magnetic resonance investigation, the ability of paramagnetic ions in aqueous solutions to cause the rapid relaxation of water protons has been recognized.'-' When biologists began to study the NMR relaxation of water protons in living tissues, they raised the question if the shortened spin-lattice relaxation time, or TI, and the spin-spin relaxation time, or T2, are significantly shortened by the presence of paramagnetic ions in the living tissues. The concensus of opinionfrom those early inquiries, expressed or implied, was that paramagnetic ions play little or no part in the shortened T I and TZ seen in virtually all living cells. However, several authors did mention that the existing knowledge could not be considered adequate enough to discount paramagnetic ion contribution to T I a n d 3 alto-gether. Among these may be mentioned Hollis et a1, Ranade et al', and Lewa and ~aczkowski.~ Nevertheless virtually allagreed that the variable water contents were a major cause of the differences observed among different tissues, normal or neoplastic.'-9 In 1980 Ling and ~ucker' ' showecLthat large differences exist among the TI'S of water protons in different living tissues even after their water contents had all been normalized to a uniform 80%. Ling and Tucker suggested that paramagnetic ion content might be an underlying cause for the difference in NMR relaxation rates of water protons of different tissues (see also in^,'^,'^ and Ling and ~ u r ~ h ~ . I 3 )
منابع مشابه
Further studies on the role of paramagnetic ion contents on the NMR relaxation time, T1 of normal tissues and cancer cells.
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ورودعنوان ژورنال:
- Physiological chemistry and physics and medical NMR
دوره 15 6 شماره
صفحات -
تاریخ انتشار 1983