Activation of biological functions in T lymphocytes is determined by the molecular dynamics occurring at the T cell/opposing cell interface. In the present study, a central question of cytotoxic T lymphocyte (CTL) biology was studied at the single-cell level: can two distinct activation thresholds for cytotoxicity and cytokine production be explained by intercellular molecular dynamics between ...

RANTES (regulated on activation, normal T expressed and secreted) is a member of the chemotactic cytokine (chemokine) beta subfamily. High affinity receptors for RANTES have been identified on a human monocytic leukemia cell line THP-1, which responded to RANTES in chemotaxis and calcium mobilization assays. Steady-state binding data analyses revealed approximately 700 binding sites/cell on THP...

B cells acquire membrane-bound cognate antigens from the surface of the APCs by forming an IS, similar to that seen in T cells. Recognition of membrane-bound antigens on the APCs initiates adhesion of B lymphocytes to the antigen-tethered surface, which is followed by the formation of radial lamellipodia-like structures, a process known as B cell spreading. The spreading response requires the r...

[(3)H]Resiniferatoxin (RTX) binding and calcium uptake by rat dorsal root ganglion (DRG) neurons show distinct structure-activity relations, suggestive of independent vanilloid receptor (VR) subtypes. We have now characterized ligand binding to rat VR1 expressed in human embryonic kidney (HEK293) and Chinese hamster ovary (CHO) cells and compared the structure-activity relations with those for ...

The administration of cholecalciferol (vitamin D3) (CC) to rachitic chicks results in the production of two major polar metabolites, 25-hydroxycholecalciferol (25-OH-CC) and 1,25-dihydroxycholecalciferol (1,25-diOH-CC), and a number of other minor metabolites. Eighteen hours after a physiological dose (0.65 mnoles) of radioactive cholecalciferol, 80% of the radioactivity in the target intestine...

cAMP can be either mitogenic or anti-mitogenic, depending on the cell type. We demonstrated previously that cAMP inhibited the proliferation of normal renal epithelial cells and stimulated the proliferation of cells derived from the cysts of polycystic kidney disease (PKD) patients. The protein products of the genes causing PKD, polycystin-1 and polycystin-2, are thought to regulate intracellul...

calcium mobilization is known to be an important factor in the activation of cells involved in inflammation,so,calcium-channel antagonists are be expected ti exhibit antiinflammatory activity.in the present study,we evaluateted the antiinflammatory effects of two calcium channel blockers,verapamil and nifedipine on adjuvant induced chronic in flammation in rat paw.sixty adult male rats were div...

AIMS The aim of the study was to obtain further information regarding the modes of action of doxazosin, naftopidil and nifedipine on platelet function. METHODS We conducted an in vitro study of drug influences on adrenaline and collagen-induced mobilization of platelet calcium. RESULTS In the presence of fibrinogen (300 micrograms ml-1) both collagen (5 micrograms ml-1) and adrenaline (16 m...

Background: Hypotension was commonly encountered in clinical practice during induction of anesthesia with propofoL The purpose of this study is to investigate the effect of propofol on mitochondrial membrane potential and morphology so as to infer its relation with intracellular calcium mobilization in bovine aortic endothelium. Methods: In this study, we used the cultured bovine aortic endothe...

Arachidonic acid (AA) liberated from membrane phospholipids is known to activate phospholipase C gamma1 (PLCgamma1) concurrently with AHNAK in nonneuronal cells. The recruitment of AHNAK from the nucleus is required for it to activate PLCgamma1 at the plasma membrane. Here, we identify the C-type natriuretic peptide receptor (NPR-C), an atypical G protein-coupled receptor, as a protein binding ...