S. Ramaprasad et Vw. Robbins, LITHIUM DISTRIBUTION IN RED-BLOOD-CELLS AND PLASMA - NMR-STUDIES OF RAT-BLOOD, Magnetic resonance imaging, 16(2), 1998, pp. 213-218
To understand the interaction of lithium (Li+) with a coadministered d
rug in both the blood and the brain, we have treated rats with either
Li+ alone or Li+ and a codrug. In this paper we address the important
problem of quantitation of intra and extracellular Li+ ion contents in
blood by the Li-7-NMR technique and the use of a shift reagent (SR).
Although Li+ can be studied by atomic absorption techniques, these tec
hniques involve tedious separation of intra-and extracellular componen
ts prior to chemical analysis, Magnetic resonance studies on rat blood
, in the dose range of 0.5 to 10 meq/kg, indicate that the intracellul
ar red blood cell Li+ predominates in the lower dose range of 0.5-1.0
meq/kg, As the lithium dose increases, a significantly larger amount o
f Li+ accumulates in the extracellular volume, Our studies on a number
of animals at various doses of LiCl indicate that Li-7-NMR of blood s
amples provide a reliable, noninvasive quantification of red blood cel
l and plasma Li+ concentrations, The NMR method was further used to st
udy the effect of coadministered drugs such as thioridazine on the int
ra-and extracellular Li+ concentration of RBCs. (C) 1998 Elsevier Scie
nce Inc.