atp-sensitive potassium (katp) channel openers have a relaxation effect due to the lower cellular membrane potential and inhibit calcium influx. there has been considerable interest in exploring katp channel openers in the treatment of various diseases such as cardiovascular, cerebrovascular, and urinary system disease and premature labor. the purpose of this study was to synthesize 3,3,6,6-tet...

Ammonia is considered the main pathogenic toxin in hepatic encephalopathy (HE). However, molecular mechanisms involved have been disputed. As altered glutamatergic and GABAergic neurotransmission has reported HE, we investigated whether four members of solute carrier 38 (Slc38) family amino acid transporters-involved replenishment glutamate GABA-contribute to ammonia neurotoxicity HE. We show t...

A Na(+)-dependent bile acid (Na+/taurocholate co-transporting polypeptide; Ntcp) and a Na(+)-independent bromosulphophthalein (BSP)/bile acid uptake system (organic-anion-transporting polypeptide; oatp) have been cloned from rat liver by using functional expression cloning in Xenopus laevis oocytes. To evaluate the extent to which these cloned transporters could account for overall hepatic bile...

Hydrolysis of ATP by Na+/K+-ATPase, a P-Type ATPase, catalyzing active Na+ and K+ transport through cellular membranes leads transiently to a phosphorylation of its catalytical α-subunit. Surprisingly, three-dimensional molecular structure analysis of P-type ATPases reveals that binding of ATP to the N-domain connected by a hinge to the P-domain is much too far away from the Asp369 to allow the...

Excitatory amino acid transporters (EAATs) remove glutamate from synapses. They maintain an efficient synaptic transmission and prevent glutamate from reaching neurotoxic levels. Glutamate transporters couple the uptake of one glutamate to the cotransport of three sodium ions and one proton and the countertransport of one potassium ion. The molecular mechanism for this coupled uptake of glutama...

Uptake and translocation of cations play essential roles in plant nutrition, signal transduction, growth, and development. Among them, potassium (K+) and sodium (Na+) have been the focus of numerous physiological studies because K+ is an essential macronutrient and the most abundant inorganic cation in plant cells, whereas Na+ toxicity is a principal component of the deleterious effects associa...

Radiocaesium (Cs) contamination of agricultural, semi-natural and natural areas is a worldwide problem that has arisen from human activities, such as intentional and unintentional discharges from the nuclear industry. The contamination of soils by Cs is of serious concern because of the long half-lives of the radionuclides (Cs = 2yr, Cs = 30yr) and the emission of harmful β and γ radiation duri...

Non-systemic drugs act within the intestinal lumen without reaching the systemic circulation. The first generation included polymeric resins that sequester phosphate ions, potassium ions, or bile acids for the treatment of electrolyte imbalances or hypercholesteremia. The field has evolved towards non-absorbable small molecules or peptides targeting luminal enzymes or transporters for the treat...

Potassium (K(+)) influx into pollen tubes via K(+) transporters is essential for pollen tube growth; however, the mechanism by which K(+) transporters are regulated in pollen tubes remains unknown. Here, we report that Arabidopsis thaliana Ca(2+)-dependent protein kinase11 (CPK11) and CPK24 are involved in Ca(2+)-dependent regulation of the inward K(+) (K(+)in) channels in pollen tubes. Using p...

The symbiosome membrane (SM) is a physical barrier between the host plant and nitrogen-fixing bacteria in the legume:rhizobia symbiosis, and represents a regulated interface for the movement of solutes between the symbionts that is under plant control. The primary nutrient exchange across the SM is the transport of a carbon energy source from plant to bacteroid in exchange for fixed nitrogen. A...