Interaction of Lanthanum and Calcium with Human Erythrocyte Membranes

The effect of lanthanum and calcium on the structure and function of human erythrocyte membranes was investigated by fluorescence polarization, spin- labeled electron spin resonance (ESR) and laser Raman spectroscopy. The results showed that low concentration of La3+ (0.5 mu mol/L) activated a Little (Na++K+)-ATPase and Mg2+-ATPase activities, and it inhibited obvi ously the ATPase activities with increasing its concentrations. La3+ lowered the lipid fluidity of human erythrocyte membranes and decreased the vibration intensity of alpha-helix of the protein in the Amide I '. The effect of Ca2+ on the lipid fluidity and alpha-helix of the protein in the Amide I ' was smaller than that of La3+.

Rb^＋ Uptake by Human Erythrocytes and Its Transmembrane Pathway

The erythrocyte hemolysis was examined to assure Rb^＋ to have a weak toxicity toward human body. The way of Rb^＋ transporting into human erythrocytes was determined, and the factors to affect this transport process were evaluated. The effects of extracellular concentration of Rb^＋, incubation temperature, incubation time, medium pH, and specific inhibitors were investigated via flame atomic absorption spectrometry. The results indicated that the membrane transport of Rb^＋ through human erythrocytes was controlled mainly by both active transport and simple diffusion. Every mentioned factor took a positive effect on the Rb^＋ uptake by human erythrocytes, however neither DIDS nor nefidpine could inhibit the uptake of Rb^＋.

Cesium＇s Affects on Morphological Changes of Human Erythrocytes

Cesium could play a toxic role in several pathological processes. Atomic force microscopy （AFM） was used to study morphological changes of human erythrocytes after incubating with different concentrations of CsCI, and the Raman spectra were used to study the effects of CsCl on the chemistry components of erythrocyte membrane. The AFM images showed that the ＂domain structures＂ that appeared after incubation with higher concentration of CsCl （150 mmol-L-1）, are featured by the particles aggregated to form ranges and the separations among them enlarged to gorges, and this change may increase the permeability of cell membranes. The Raman results showed that the polar part of membrane phospholipid become more order and with the increasing of the concentration of CsCl, the longitudinal order of nonpolar parts first decreased and then increased. It is concluded that the aggregation of mem- brane proteins and the order changes of the phospholipid cause a change in the distribution and conformation of the phospholipid membrane. And the effects of CsCl on the erythrocyte membrane are mainly dependent on its concentration.

Transmembrane Ca^(2+) gradient and human erythrocyte cell skeleton

The cytosolic free Ca2+ in erythrocytes is around 10-6 mol/L, whereas the extracellularCa2+ concentration is about 10-3 mol/L. Thus it results in 1000-fold transmembraneCa2+ gradient across erythrocyte membrane. Our previous results have shown

Preclinical trials of human erythrocyte superoxide dismutase injection

To assess the quality of human erythrocyte superoxide dismutase (SOD) injection reaching the official standard for its clinical uses Methods Human erythrocyte SOD injection prepared by McCord Fridovich's method without column chromatography but with some modifications was used in preclinical trials, to observe the general pharmacology and pharmacodynamics of the product Results The quality of human erythrocyte SOD injection conformed to the official standard of a biological product, which was found to be non toxic and did not have any effects on the central and autonomic nervous systems as well as cardiovascular and respiratory systems The efficacy of anti inflammation and promotion of immuno regulation especially on carrageenan and adjuvant induced polyarthritis were shown in animals Conclusion Human erythrocyte SOD injection is appropriate for prophylactic and therapeutic uses in clinical trials

Domain-domain communication in Band 3 of human erythrocytes

Band 3, serving as an anion transporter, is the most abundant protein in the humanerythrocyte plasma membrane. It has two strucurally and functionally distinct domains.The membrane domain is responsible for the anion exchange activity, while thecytoplasmic domain of Band 3 binds with components of the cytoskeleton (such asankyrin) to stabilize the cytoskeleton network. Although the cytoplasmic domain is