Cell-attached and whole cell recording techniques were used to study the effects of electrogenic sodium pump on the excitability of rat suprachiasmatic nucleus (SCN) neurons. Blocking the sodium pump with the cardiac steroid strophanthidin or zero K+ increased the spontaneous firing of SCN neurons to different degrees with different recording modes, whereas turning the sodium pump into a nonsel...

In virtually all mammalian cells, the traditional roles of the Na/K pump include establishing and maintaining transcellular gradients of Na and K and modulating steady-state gradients of H and Ca. By regulating intracellular Na, [Na]i, the Na/K pump also makes a major contribution to cellular volume control, although some aspects of this modulation of osmolarity are not completely understood (A...

In virtually all mammalian cells, the traditional roles of the Na/K pump include establishing and maintaining transcellular gradients of Na and K and modulating steady-state gradients of H and Ca. By regulating intracellular Na, [Na]i, the Na/K pump also makes a major contribution to cellular volume control, although some aspects of this modulation of osmolarity are not completely understood (A...

The Na(+)-K(+) pump in the erythrocytes of a mordibly obese patient shows a unique constellation of functional abnormalities. The number of pump units, measured by [(3)H]ouabain binding to intact cells, as well as the enzymatic activity of the (Na(+)-K(+))-dependent ATPase in erythrocyte membranes were found to be markedly increased compared with control cells (18-fold and 14-fold, respectively...

A modest diet-induced increase in serum cholesterol in rabbits increases the sensitivity of the sarcolemmal Na+/K+ pump to intracellular Na+, whereas a large increase in cholesterol levels decreases the sensitivity to Na+. To examine the mechanisms, we isolated cardiac myocytes from controls and from rabbits with diet-induced increases in serum cholesterol. The myocytes were voltage clamped wit...

The (Na+,K+) ATPase in plasma membranes isolated from rat adipocytes is insensitive to insulin (Lytton J., Lin, J.C., and Guidotti, G. (1985) J. Biol. Chem. 260, 1177-1184). For this reason, the characteristics of the (Na+,K+) pump in adipocyte ghosts, prepared by hypotonic lysis of adipocytes (Rodbell, M. (1967) J. Biol. Chem. 242, 5744-5750), were studied. Herein it is demonstrated that the (...

Long-term exposure to cocaine can cause persistent behavioral changes and alterations in neuronal function. One cocaine-regulated mRNA in the rat brain is the beta-1 subunit of the Na+/K(+)-ATPase pump. We examined both Na+/K(+)-ATPase function and expression after cocaine treatment of pheochromocytoma cells. One-hour exposure to cocaine did not alter Na+/K(+)-ATPase activity, as measured by th...

Ionic concentrations fluctuate significantly during epileptic seizures. In this study, using a combination of in vitro electrophysiology, computer modeling, and dynamical systems analysis, we demonstrate that changes in the potassium and sodium intra- and extracellular ion concentrations ([K(+)] and [Na(+)], respectively) during seizure affect the neuron dynamics by modulating the outward Na(+)...

Kim, Moon Young, Geun Hee Seol, Guo Hua Liang, Ji Aee Kim, and Suk Hyo Suh. Na -K pump activation inhibits endothelium-dependent relaxation by activating the forward mode of Na /Ca exchanger in mouse aorta. Am J Physiol Heart Circ Physiol 289: H2020–H2029, 2005. First published July 1, 2005; doi:10.1152/ajpheart.00908.2004.—The effect of Na -K pump activation on endothelium-dependent relaxation...

The goal of this study was to assess the role of the electrogenic Na+-K+ pump in controlling active tone in cremasteric arterioles of normotensive hamsters and hamsters with bilateral (two-kidney, two figure-8) Grollman hypertension. Arterioles of both groups exhibited a large transient dilation when the Na+-K+ pump was stimulated by superfusing the cremaster muscle with physiological salt solu...