The Na/K-ATPase has been shown to bind 1 and 0.5 mol of (32)P/mol of alpha-chain in the presence [gamma-(32)P]ATP and [alpha-(32)P]ATP, respectively, accompanied by a maximum accumulation of 0.5 mol of ADP-sensitive phosphoenzyme (NaE1P) and potassium-sensitive phosphoenzyme (E2P). The former accumulation was followed by the slow constant liberation of P(i), but the latter was accompanied with ...

Valinomycin-induced uptake of rubidium by membrane vesicles prepared from Escherichia coli, Staphylococcus QUreus, and Micrococcus denifrificans is analogous in nearly all respects to the transport of sugars or amino acids, or both, by these membrane vesicles. In E. coli membrane vesicles, concentrative rubidium uptake is stimulated maximally by D-lactate and by the artificial electron donor as...

Significant correlation has been shown between the severity of coronary disease and level of coronary blood flow as measured by the rubidium coincidence technique. Contrary to the commonly expressed view, however, the rubidium coincidence method does not evaluate nutritional flow, but estimates total coronary blood flow (CBFT). An equation is derived that does evaluate nutritional flow (CBFN), ...

To study the relationship of the serum digoxin concentration to the digoxin effect on monovalent cation transport during the quinidine-digoxin interaction, we used radiolabeled rubidium to measure monovalent cation active transport in myocardial biopsy samples from dogs. In a preliminary study, we showed that quinidine did not affect rubidium uptake by myocardial samples from intact dogs. Then,...

The uncoupling activity of nigericin in rat liver mitochondria was found to be proportional to the external concentration of potassium. Rubidium (40% as effective as potassium) was the only other alkali metal cation that permitted significant uncoupling. The ability of nigericin selectively to inhibit (at low concentrations) and to uncouple (at high concentrations) only certain substrates was i...

Net taurine transport across the frog retinal pigment epithelium-choroid was measured as a function of extracellular potassium concentration, [K+]o. The net rate of retina-to-choroid transport increased monotonically as [K+]o increased from 0.2 mM to 2 mM on the apical (neural retinal) side of the tissue. No further increase was observed when [k+]o was elevated to 5 mM. The [K+]o changes that m...

Studying carbon, with its many allotropes and compounds, is one of the most fascinating problems in science. To mention only physics, before graphene, which was awarded the Nobel prize in 2010 opening exciting perspectives for fundamental and applied research, many other systems, such as nanotubes, fullerenes and intercalated graphites have played an important role in several fields, including ...

The influence of alkali-metal ions on the incorporation of labeled precursors into phospholipids and triglycerides was studied in rat liver slices. By use of acetate-l-G4 and ~a1mitate-l-C~~ as lipid precursors, a comparison was made of the pathway from acetate to phospholipid and the pathway from palmitate to phospholipid. While the rate of incorporation of palmitate-l-C1* into phospholipids a...

In the title complex, [Rb(C(36)H(61)O(11))]·2H(2)O, the Rb(+) cation is coordinated by seven O atoms of monensin. Rb-O distances range from 2.7870 (17) to 3.1429 (17) Å. Both O atoms of the carboxyl-ate group are involved in the coordination of Rb. The structure displays inter- and intra-molecular O-H⋯O and C-H⋯O hydrogen-bonding inter-actions.