Lipid Lithium

K = 63 M 1, Kb = 1.4M-1)47 lithium-7 (K = 14 M 1 K" = 0.5 M 1) 49) and for cesium-133 (K, st 50 M-1, K = 4M 1)S0). In the case of sodium-23, transverse relaxation times could also be utilized to determine off-rate constants k ff = 3 x 105/sec k"ff = 2x 107/sec47,51). Therefore for sodium ion four of the five rate constants have been independently determined. What has not been obtained for sodium ion is the rate constant for the central barrier, kcb. By means of dielectric relaxation studies a rate constant considered to be for passage over the central barrier, i.e. for jumping between sites, has been determined for Tl+ to be approximately 4 x 106/sec 52). If we make the assumption that the binding process functions as a normalization of free energies, recognize that the contribution of the lipid to the central barrier is independent of the ion and note that the channel is quite uniform, then it is reasonable to utilize the value of 4x 106/sec for the sodium ion. 

Newer uses have appeared in the treatment of viral diseases including AIDS, alteration of the immune response, and cancer. The lithium salt of 7-linolenic acid (LiGLA) has a significant anticancer effect against certain cancers. The neurochemical basis for lithium action is difficult to define. Lithium carbonate induces a wide range of intra- and extracellular changes—most emphasis has been naturally on the similarities with Na/K/Ca/Mg ions. Lithium selectively interferes with the inositol lipid cycle, representing a unified hypothesis of action. The biochemistry, distribution, and cellular localization of lithium has been extensively documented. 

Solvent extraction of the total lipid extracts from ceramic sherds and charred surface residues Isolation of DAGs and TAGs on silica solid phase cartridges Formation of lithiated adducts from the TAG fraction by addition of 2% lithium chloride in methanol... 

The mechanism of action of U ions remains to be fully elucidated. Oiemi-cally, lithium is the lightest of the alkaU metals, which include such biologically important elements as sodium and potassium. Apart from interference with transmembrane cation fluxes (via ion channels and pumps), a lithium effect of major significance appears to be membrane depletion of phosphatidylinositol bisphosphates, the principal lipid substrate used by various receptors in transmembrane signalling (p. 66). 

Dioxanes can be opened by an arene-catalyzed lithiation only if the carbon-oxygen bond to be cleaved occupies an allylic or benzylic position. This is the case of the vinyl-dioxane 416, which reacted with lithium and a catalytic amount of DTBB in THE at 0 °C, and the allylic intermediate 417 generated reacted at the y -position with tridecyl iodide to yield the compound 418, used in the synthesis of plasmenyl-type lipids (Scheme 117) . 

Lithium compounds, bis(trimethylsilyl) peroxide reactions, 796-8, 799 Liver diseases, lipid hydroperoxides, 613 Liver microsomes, 4-hydroxynon-2-enal, 613-14... 

Drummond AH, Raeburn CA The interaction of lithium with thyrotropin releasing hormone-stimulated lipid metabolism in GH3 pituitary tumor cells. Biochem J 224 129-136, 1984... 

The second enzyme of the cycle, N-acetylglucosaminetransferase, was extracted from Bacillus megaterium membranes with lithium chloride,428 and extensively purified.429 The activity of the enzyme is also stimulated by addition of lipids. 

SCHEME 14.8 Synthesis of the Re-type lipid A from Escherichia coli. DCC, A,A -dicyclo-hexylcarbodiimide DMAP, 4-dimethylaminopyridine LHMDS, lithium bis(trimethylsilyl) amide TES, triethylsilyl. 

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