40 41 Na/K pump activity and metabolic rate are both higher at day in the suprachiasmatic nucleus 42 (SCN) that houses the circadian clock. Here we investigated the role of intracellular Na and 43 energy metabolism in regulating Na/K pump activity and neuronal excitability. Removal of 44 extracellular K to block the Na/K pump excited SCN neurons to fire at higher rates and return 45 to normal K...

During excitation, muscle cells gain Na(+) and lose K(+), leading to a rise in extracellular K(+) ([K(+)]o), depolarization, and loss of excitability. Recent studies support the idea that these events are important causes of muscle fatigue and that full use of the Na(+),K(+)-ATPase (also known as the Na(+),K(+) pump) is often essential for adequate clearance of extracellular K(+). As a result o...

1 A specific and essential role for Na,K-ATPase α3 in neurons co-expressing α1 and α3* Background: Neurons express two Na,K-ATPase isoforms, the ubiquitous α1 and neuron-specific α3. Result: α3 is important for control of membrane potential and is fully responsible for restoration of large [Na + ] i increases. Conclusion: α1 and α3 are required for basal neuronal function, but α3 controls resto...

in a greenhouse experiment, the effects of waterlogging, sewage sludge and manure on the uptake and concentrations of p, k, ca, mg and na in root and shoot of sunflower (helianthus annuus l.) were investigated. a factorial experiment based on completely randomized design with three replications including duration of waterlogging at five levels (0, 2, 4, 8, 22 days), source of organic fertilizer...

Voltage-gated potassium (K+) channels are multi-ion pores. Recent studies suggest that, similar to calcium channels, competition between ionic species for intrapore binding sites may contribute to ionic selectivity in at least some K+ channels. Molecular studies suggest that a putative constricted region of the pore, which is presumably the site of selectivity, may be as short as one ionic diam...

Na,K-ATPase is a hetero-oligomer of an aand a b-subunit. The a-subunit (Na,K-a) possesses the catalytic function, whereas the bsubunit (Na,K-b) has cell-cell adhesion function and is localized to the apical junctional complex in polarized epithelial cells. Earlier, we identified two distinct conserved motifs on the Na,K-b1 transmembrane domain that mediate protein-protein interactions: a glycin...

Gomes, Pedro, and Patrı́cio Soares-da-Silva. Upregulation of apical NHE3 in renal OK cells overexpressing the rodent 1-subunit of the Na pump. Am J Physiol Regul Integr Comp Physiol 290: R1142–R1150, 2006. First published November 17, 2005; doi:10.1152/ajpregu.00102.2005.— Vectorial Na reabsorption across the proximal tubule is mediated by apical entry of Na , primarily via Na /H exchanger isofo...

Ouabain inhibited 86RbCl uptake by 80% in rabbit gastric superficial epithelial cells (SEC), revealing the presence of a functional Na+,K+-ATPase [(Na+ + K+)-transporting ATPase] pump. Intact SEC were used to study the ouabain-sensitive Na+,K+-ATPase and K+-pNPPase (K+-stimulated p-nitrophenyl phosphatase) activities before and after lysis. Intact SEC showed no Na+,K+-ATPase and insignificant M...

Na/K pump current was determined between -140 and +60 mV as steady-state, strophanthidin-sensitive, whole-cell current in guinea pig ventricular myocytes, voltage-clamped and internally dialyzed via wide-tipped pipettes. Solutions were designed to minimize all other components of membrane current. A device for exchanging the solution inside the pipette permitted investigation of Na/K pump curre...

Introduction: To assess the salivary composition of proteins and minerals in smokers compared with non-smokers.   Materials and Methods: In this study we compared the total protein and Ca, Na, K, Mg, Pb of whole saliva in two groups of men (28 smokers and 31nonsmokers) aged between 29-41years.   Results: Fifty-nine participants were evaluated. The mean age was 33.14±5.32 years among smo...