The electrophysiological and metabolic responses to insulin of skeletal muscles from control and potassium-depleted rats were compared. Membrane potentials, action potentials, contraction parameters as well as oxygen uptake were measured in diaphragm strips or intact extremity muscles from the two groups, and similar measurements were made in vivo. The muscles were examined in solutions with no...

this study was conducted to explore the effects of drought stress and different levels of potassium sulfate on yield and yield attributes of grain sorghum at agriculture and natural resources research station of sistan during year of 2009. treatments were arranged in a split-plot lay out based on a randomized complete block design with three levels of drought stress as main plot (irrigation at ...

The effects of nano particles of CuO on voltage-dependent potassium currents were studied in acutely isolated CA1 pyramidal neurons of rat hippocampus using the whole-cell patch-clamp techniques. Nano particles of CuO had small effects on transient outward potassium current (I(A), no statistical significance) and mainly inhibited delayed rectifier potassium current (I(K)) in the concentration o...

Because plants grow under many different types of soil and environmental conditions, we investigated the hypothesis that multiple pathways for K+ uptake exist in plants. We have identified a new family of potassium transporters from Arabidopsis by searching for homologous sequences among the expressed sequence tags of the GenBank database. The deduced amino acid sequences of AtKUP (for Arabidop...

Maintenance of extracellular K(+) concentration within a narrow range is vital for numerous cell functions, particularly electrical excitability of heart and muscle. Potassium homeostasis during intermittent ingestion of K(+) involves rapid redistribution of K(+) into the intracellular space to minimize increases in extracellular K(+) concentration, and ultimate elimination of the K(+) load by ...

Larvae of Manduca sexta were fed on tobacco leaves or synthetic diets with differing potassium content. For all diets tested, midgut lumen K+ activity coefficients were low, and midgut lumen K+ activities, K+ concentrations and pH values were as closely regulated as in blood. The transmidgut electrochemical potential difference for potassium based on activities was lower than had previously bee...

Kinetics of two molecular forms of K-dependent citrate dehydrase in maize (Zea mays L.) are reported. The isozymes, designated CD I and CD II, were found to be compartmented in mitochondria and cytosol, respectively.CD I exhibited hyperbolic kinetics with respect to both citrate and potassium with K(m) 2.3 and 12 millimolar, respectively. Maximum velocity was 0.38 micromole of trans-aconitic ac...

The availability of potassium to the plant is highly variable, due to complex soil dynamics, which are strongly influenced by root-soil interactions. A low plant potassium status triggers expression of high affinity K+ transporters, up-regulates some K+ channels, and activates signalling cascades, some of which are similar to those involved in wounding and other stress responses. The molecules ...

Estimates of initial binding rates for [3H]ouabain interaction with (Na+ + K+)-ATPase were obtained in the presence of ATP, magnesium, sodium, and potassium by using short assay times at 30”. The reactions were terminated by the rapid addition of excess unlabeled ouabain; this did not appear to displace bound [3H]ouabain during subsequent treatment of the suspensions (prior to assay). Initial b...

Potassium taurine bicarbonate (PTB), an equimolar blend of potassium bicarbonate and taurine, provides a convenient and feasible means of delivering physiologically significant doses of potassium, taurine, and organic base when dissolved in water (“Kwater”). This brief essay reviews the versatile and complementary health benefits that likely would accrue in individuals making regular use of K-w...