Disease relevance of lanthanum

• Lanthanum probe studies of cellular pathophysiology induced by hypoxia in isolated cardiac muscle [1].
• Suppression of experimental atherosclerosis by the Ca++-antagonist lanthanum. Possible role of calcium in atherogenesis [2].
• CONCLUSIONS: Experimental colitis is associated with hepatobiliary complications and an increased hepatocyte tight junctional permeability to horseradish peroxidase and lanthanum [3].
• At 2 hrs post infarction, ischemic muscle showed: 1) loss of membrane-bound acid phosphatase and aryl sulfatase; 2) mitochondrial damage; 3) loss of glycogen and disappearance of I but not A bands; and 4) entry into cells of colloidal lanthanum (= loss of plasma membrane integrity [4].
• The presence of these unique structures in the renal tumor and its abdominal metastases was demonstrated by electron microscopy with the use of lanthanum impregnation [5].

Psychiatry related information on lanthanum

• The duration of the first such phase, called short-term memory, is increased when the intracranial calcium ion concentration is raised and the phase is practically abolished by injection of lanthanum ions [6].
• The calcium channel blocker, lanthanum chloride, also inhibited the formation of short-term memory, with amnesia still present as late as 24 h following learning [7].
• The tumour growth, dehydration and burning of rats as well as sleep deprivation, overheating, lanthanum and ruthenium red have been shown to cause changes in the activity of some enzyme-systems located in endoplasmic reticulum [8].

High impact information on lanthanum

• HERG current is K+ selective, declines with depolarizations above 0 mV, is activated by extracellular K+, and is blocked by lanthanum [9].
• The channel is indistinguishable from ICRAC in the following features: sequence of selectivity to divalent cations; an anomalous mole fraction effect; whole-cell current kinetics; block by lanthanum; loss of selectivity in the absence of divalent cations; and single-channel conductance to Na+ in divalent-ion-free conditions [10].
• In these experiments, up to 79% of the total tissue sialic acid was removed, and electron microscopy studies showed that this removal was accompanied by marked reduction of lanthanum binding to the sarcolemma [11].
• Initiation of meiotic maturation in Xenopus laevis oocytes by lanthanum [12].
• Calcium influx requirement for human neutrophil chemotaxis: inhibition by lanthanum chloride [13].

Chemical compound and disease context of lanthanum

• When mice were sensitized with dinitrofluorobenzene on skin sites pretreated with topical lanthanum chloride, and challenged on untreated ear skin, a markedly reduced contact hypersensitivity response was observed [14].
• In a randomised 1-year trial, numerically fewer lanthanum carbonate (elemental lanthanum < or =3750 mg/day) recipients had renal bone disease at study end than at baseline; however, in the calcium carbonate < or =9000 mg/day group, numerically more patients had renal bone disease at study end compared with baseline [15].
• The effects of lanthanum and gadolinium on currents evoked by excitatory amino acids were studied in cultured rat hippocampal and cortical neurons, in freshly dissociated dorsal root ganglion neurons, and in human embryonic kidney 293 cells expressing the GluR6 kainate receptor subunit [16].
• 4. The blockade of the Na(+)-Ca2+ exchanger by the amiloride derivative 5-(N-4-chlorobenzyl)-2',4'-dimethylbenzamil (CB-DMB), lanthanum (La3+) and the Ca2+ chelator EGTA, completely reverted the protective effect exerted by the removal of Na+ ions on C6 glioma cells exposed to chemical hypoxia [17].
• Low concentrations of lanthanum (0.1-0.5 mM) augmented the caffeine contracture [18].

Biological context of lanthanum

• Lanthanum in concentrations that suppressed chemotaxis also inhibited the calcium influx caused by activated serum [13].
• The LTD4-induced increases in [Ca+2]i were dependent on extracellular calcium and diminished by lanthanum, but not affected by nifedipine nor associated with changes in membrane potential, as measured with the fluorescent probe 3,3'-dipentyloxacarbocyanine [19].
• Lanthanum, however, produce little or no change in cell plate initiation or the rate of chromosome motion [20].
• CapG-null macrophages also demonstrate approximately 50% impairment of immunoglobulin G, and complement-opsonized phagocytosis and lanthanum-induced vesicle rocketing [21].
• In Arabidopsis, lanthanum or EGTA caused a partial inhibition of both cold shock [Ca2+]cyt elevation and cold-dependent kin1 gene expression [22].

Anatomical context of lanthanum

• Permeability of paracellular shunt pathways is increase by transmucosal osmotic gradients, and in certain epithelia these changes are associated with bullous-like deformations (blisters) of the zonula occludens and localization of lanthanum within junctional complexes [23].
• Localization of lanthanum in the junctional complexes of fasted control animals was not observed, whereas approximately equal to 50% of the zonula occludens in DHC-infused animals contained lanthanum which was also occasionally identified within the lumen of the bile canaliculus [23].
• These results indicate that infusions of DHC cause blisters adjacent to the junctional complex of rat hepatocytes in association with changes in solute conductivity of the zonula occludens to cations such as ionic lanthanum chloride, and presumably to larger solutes such as sucrose [23].
• A concurrent increase in lanthanum permeability between nonnecrotic surface mucous epithelial cells was also demonstrated [24].
• Electron microscopy revealed extensive alteration of the brush border membrane with a decrease in binding of lanthanum and the development of permeability to tracer in villus tip cells [25].

Associations of lanthanum with other chemical compounds

• This glucose effect was also dependent on extracellular calcium and pH, since these calcium changes were inhibited in an acidotic or a calcium-free medium, or by the competitive calcium antagonist lanthanum [26].
• In separate groups of animals 5 mM ionic lanthanum chloride was perfused intraportally after taurodehydrocholate infusions, and the number of junctional complexes that contained the electron dense marker were quantitated by transmission electron microscopy [23].
• Calcium uptake into human intestinal brush border membrane vesicles represented uptake into intravesicular space as evidenced by studies of osmolality, temperature dependence, calcium ionophore A23187-induced efflux and influx, and lanthanum displacement [27].
• The effect of PMN migration on epithelial permeability was examined using the ultrastructural tracers HRP and lanthanum nitrate [28].
• Perturbation of the cellular Ca++ distribution by treatment with lanthanum, procaine, or EGTA results in a loss of diffuse fluorescence with no accompanying change in the intensity of punctate fluorescence [29].

Gene context of lanthanum

• Protection of SH-SY5Y cells against MPP(+) was significantly decreased upon the overexpression of antisense TRPC1 cDNA construct or the addition of a nonspecific transient receptor potential channel blocker lanthanum [30].
• Absence of a functional IL-10 gene in IL-10KO mice resulted in a significant augmentation of apical diffusion of lanthanum after DNBS-induced colitis [31].
• Zinc-induced apoptosis was independent of inhibition of PKA, PKC, guanylate cyclase and MAPK, but it was suppressed in the presence of 100 microM lanthanum chloride [32].
• Lanthanum (La3+) depresses IGFBP release from all three cell types (> 80% for GM10 and T98G cells and > 65% for MDBK cells) [33].
• Furthermore, somatostatin enhanced the uptake of 45calcium in renal cortical slices which could be blocked by lanthanum, an inhibitor of Ca2+ influx [34].

Analytical, diagnostic and therapeutic context of lanthanum

• CTC fluorescence of freshly teased crayfish claw muscle sarcoplasmic reticulum coincides with the A bands and is reduced by perfusion with lanthanum, procaine, and EGTA in a manner similar to that for diffuse fluorescence in the endosperm cells [29].
• [Ca]i, defined as Ca not displaceable by lanthanum, was measured by atomic absorption spectrophotometry [35].
• Similar to smooth muscle cells, valvular interstitial cells are extensively coupled by communicating junctions as shown by thin sections, freeze-fracture, lanthanum staining, and carboxyfluorescein microinjection [36].
• Experiments with lanthanum chloride (250 microm) showed that adhesion strength was dependent on entry of calcium ions subsequent to N-cadherin ligation [37].
• The aim of this study was to investigate the effects of lanthanum carbonate on bone histology in NRF and CRF rats after oral administration of the compound with doses of 100, 500, or 1000 mg/kg per d for 12 wk [38].

References