ATP binding cassette (ABC) transporters are ATP-dependent membrane proteins predominantly expressed in excretory organs, such as the liver, intestine, blood-brain barrier, blood-testes barrier, placenta, and kidney. Here, they play an important role in the absorption, distribution, and excretion of drugs, xenobiotics, and endogenous compounds. In addition, the ABC transporters, P-glycoprotein (...

Mitochondrial calcium (Ca ) dyshomeostasis constitutes a critical step in the metabolic crossroads leading to cell death. Therefore, we have studied here whether 7-chloro-5-(2-chlorophenyl)-1,5-dihydro-4,1-benzothiazepin-2(3H)-one (CGP37157; CGP), a blocker of the mitochondrial Na /Ca -exchanger (mNCX), protects against veratridine-elicited chromaffin cell death, a model suitable to study cell ...

In human bronchial muscle preparations, nifedipine (3 mM) significantly inhibited the histamine, ACh and KCl contractions. However, the dihydropyridine did not modify the contractile responses induced by either leukotriene D4 (LTD4) or antihuman IgE (a-IgE). In human airways, SK&F 96365 (30 mM and 100 mM) markedly reduced the KCl and, at the higher concentration, LTD4 maximal contractions. In a...

The purpose of the present study was to investigate the effects of Ca sensitizers EMD 57033, MCI-154, and EGIS-9377 in cardiac preparations from streptozotocin-induced diabetic rats. In enzymatically dissociated ventricular myocytes loaded with the Ca probe indo 1, these Ca sensitizers caused an increase in cell shortening without a significant effect on the intracellular Ca ([Ca]i) transient. ...

Using intestinal (Caco-2) cells, we found that oxidant-induced disruption of barrier integrity requires microtubule disassembly. Protein kinase C (PKC)isoform seems to be essential for disruption, but the mechanism is unknown. Because inducible nitric-oxide synthase (iNOS) is key to oxidant stress, we hypothesized that PKCactivation is essential in oxidant-induced iNOS up-regulation and the con...

Bacterial lipopolysaccharide (LPS) activates the immune system and promotes inflammation via Toll-like receptor (TLR) 4, which regulates the synthesis and release of tumor necrosis factor (TNF)and other inflammatory cytokines. Previous studies have shown that the nucleoside adenosine suppresses LPS-stimulated TNFrelease in human UB939 macrophages by activating an adenosine A3 receptor (A3AR) su...

Transporter proteins in biological membranes may be divided into channels and carriers. Channels function as selective pores that open in response to a chemical or electrophysiological stimulus, allowing movement of a solute down an electrochemical gradient. Active carrier proteins use an energy producing process to translocate a substrate against a concentration gradient. Secondary active tran...

Type 2 diabetes has become a pervasive public health problem. The etiology of the disease has not been fully defined but appears to involve abnormalities in peripheral and central nervous system pathways, as well as prominent inflammatory components. Because nicotinic acetylcholine receptors (nAChRs) are known to interact with anti-inflammatory pathways and have been implicated in control of ap...

The effects of the 5d energy locations of Ce centers on the NIR quantum cutting process were studied in Y2SiO5 with two different substitutional Y lattice sites for Ce and Yb. Powder XRD and Rietveld refinement were used to characterize phase purity, crystal structure, lattice parameters and occupation fractions of Y2-x-yCexYbySiO5 (x = 0.002 and 0.3, y = 0-0.2). PLE and PL spectra show that bo...

Activation of G protein-coupled receptors (GPCRs) may bring about their disappearance from the cell membrane, and it is commonly accepted that G protein-coupled receptor kinases (GRKs) play a key function in this mechanism. Opioid receptors belong to the family of GPCRs and are substrates of GRKs. We examined the fate of and -opioid receptors and GRK2 and 3 in living cells during the process of...