[Accumulation of sodium and potassium ions in oocytes of the river lamprey Lampetra fluviatilis during prespawning period].

Accumulation of Na+ and K+ ions in oocytes of the river lamprey Lampetra fluviatilis and their transport across the plasma membrane is realized by two main mechanisms--Na,K-pump and Na,K,Cl-cotransport. At the prespawning period from December to May the intracellular Na+ concentration was observed to increase from 10 to 25 mM and the K+ concentration--from 28 to 45 mM. Results obtained on isolated oocytes with aid of 204Tl radioactive label have shown that contributions of the Na,K-pump and Na,K,Cl-cotransport to potassium accumulations were close until March.

[Transport of monovalent thallium across the membrane of oocyte of the lamprey Lampetra fluviatilis].

Mechanisms of transport of monovalent thallium across the membrane of oocyte of the lamprey Lampetra fluviatilis were studied by using 204Tl. Transport of Tl+ in lamprey oocytes has been shown to be realized by at least two pathways: through Na/K-pump and by the mechanism of Na,K,Cl-cotransport. In the standard Ringer solution (mM): 4 KCl, 140 NaCl, 0.

[Kinetic properties of sodium transport pathways in the river lamprey Lampetra fluviatilis erythrocytes].

To activate Na+/H+ exchange, intracellular pH (pHi) of erythrocytes of the river lamprey Lampetra fluviatilis were changed from 6 to 8 using nigericin. The Na+/H+ exchanger activity was estimated from the values of amiloride-sensitive components of Na+ (22Na) inflow or of H+ outflow from erythrocytes. Kinetic parameters of the carrier functioning were determined by using Hill equation.

[Characteristics of certain components of the systemic inflammatory reaction in patients with diffusive peritonitis].

The clinical, immunobiochemical and hemostasiological parameters of the systemic inflammatory response (SIR) were studied in 51 patients with diffusive peritonitis. The study showed that lactoferrin, plasminogen/plasmin and alpha 2-macroglobulin can be used, in a set, as informative indices of SIR. A reduced content of lactoferrin, a smaller concentration of proteases inhibitor alpha 2-macroglobulin and a higher relation between plasminogen and plasmin correlate with an unfavorable outcome of the disease beginning from the 1st postoperative day.

Activation of potassium channels in erythrocytes of marine teleost Scorpaena porcus.

To assess the possibility of stimulating Ca2+-activated K+ channels, marine fish erythrocytes were incubated at 20-22 degrees C in saline containing a Ca2+-ATPase inhibitor (orthovanadate), a Ca2+ ionophore (A23187), propranolol or Pb2+. Incubation of the cells for up to 2 h under control conditions or in the presence of 5 mM NH4VO3 and 1 mM Ca2+ did not affect the intracellular K+ and Na+ concentrations. About 50% cellular K+ was lost from erythrocytes incubated in the presence of 0.

Chloride transport in red blood cells of lamprey Lampetra fluviatilis: evidence for a novel anion-exchange system.

The existence of a furosemide-sensitive Cl- transport pathway activated by external Ca2+ and Mg2+ has been demonstrated previously in studies of Cl- influx across the lamprey erythrocyte membrane. The aim of the present study was to characterize further specific Cl- transport pathways, especially those involved in Cl- efflux, in the red blood cell membrane of Lampetra fluviatilis. Cl- efflux was inhibited by 0.

Potassium channels of the lamprey erythrocyte membrane exhibit a high selectivity to K+ over Rb+: a comparative study of 86Rb and 41K transport.

In order to assess the specificity of potassium channels, we examined the K+ transport pathways in the lamprey red blood cells using 86Rb and stable isotope 41K as tracers measured by the mass spectrometric method. Upon replacing 4 mmol/l K+ with 4 mmol/l Rb+ in the incubation medium, the rate coefficient for unidirectional 86Rb influx (Kin) was significantly reduced from 1.48 +/- 0.

Chloride transport in red blood cells of lamprey lampetra fluviatilis: evidence for a novel anion-exchange system.

The existence of a furosemide-sensitive Cl- transport pathway activated by external Ca2+ and Mg2+ has been demonstrated previously in studies of Cl- influx across the lamprey erythrocyte membrane. The aim of the present study was to characterize further specific Cl- transport pathways, especially those involved in Cl- efflux, in the red blood cell membrane of Lampetra fluviatilis. Cl- efflux was inhibited by 0.

An amiloride-sensitive, volume-dependent Na+ transport across the lamprey (Lampetra fluviatilis) erythrocyte membrane.

Na+ transport across the lamprey erythrocyte membrane was examined using 22Na as a tracer. Both Na+ influx and Na+ effux exhibit a wide variability among different lampreys due to amiloride-sensitive components. Addition of 1 mmol/l amiloride to incubation media resulted in a decrease of the Na+ influx from 8.

Effect of metabolic inhibitors on K+ transport across the lamprey (Lampetra fluviatilis) erythrocyte membrane.

In order to assess the contribution of oxidative metabolism to K+(86Rb+) transport across the lamprey red cell membrane, the effects of various metabolic inhibitors were examined. The influx of K+ was reduced markedly in the presence of 20 mumol/l 2,4-dinitrophenol (2,4-DNP) or rotenone, and to a lesser extent by 1 mmol/l cyanide. Rotenone produced complete inhibition of the K+ active transport and a partial blockade of K+ channels by 28% on the average.

Anion-dependent transport of thallous ions through human erythrocyte membrane.

Undirectional fluxes of 204Tl+ through the human red blood cell membrane were measured. The inward rate coefficient measured in a K(+)-free saline was 15.6 +/- 0.

Potassium transport in lamprey (Lampetra fluviatilis) erythrocytes: evidence for K+ channels.

1. Unidirectional K+ (86Rb) influx in lamprey red blood cells was studied under different conditions. 2.

[The transport of univalent thallium across the human erythrocyte membrane].

Transport of 204Tl was studied in human erythrocytes incubated in isotonic salt solutions at pH 7.4 and 37 degrees C. 204Tl was rapidly accumulated in cells up to the constant level within a 10 minutes incubation (t0.