The effects of the Ca2+ channel blockers verapamil, nifedipine, and diltiazem on triiodothyronine (T3) and thyroxine (T4) uptake were tested in cultured cardiomyocytes from 2-day-old rats. Experiments were performed at 37 degrees C in medium with 0.5% BSA for [125I]T3 (100 pM) or 0.1% BSA for [125I]T4 (350 pM). The 15-min uptake of [125I]T3 was 0.124 +/- 0.013 fmol/pM free T3 (n = 6); [125I]T4 ...

The acid saline extract (ASE) of rat submaxillary gland exerts a powerful degrading effect on 125I-glucagon. In order to study the degradation of other 125I-peptides by ASE and the effects of their inhibitors, 125I-pancreatic polypeptide (PP) and 125I-insulin were used together with 125I-glucagon. The degradation studies were done by the trichloroacetic acid (TCA) method or gel filtration. Besi...

Low density lipoprotein (LDL) modified by incubation with phospholipase C (PLC-LDL) aggregates in solution and is rapidly taken up and degraded by human and mouse macrophages, producing foam cells in vitro. Human, mouse, and rabbit macrophages degraded 125I-labeled PLC-LDL (125I-PLC-LDL) more rapidly than native 125I-labeled LDL (125I-LDL), while nonphagocytic cells such as human fibroblasts an...

A new design of 125I (Model IR-Seed2) brachytherapy source has been manufactured recently at the Applied Radiation Research School, Nuclear Science and Technology Research Institute in Iran. The source consists of six resin beads (0.5 mm diameter) that are sealed in a cylindrical titanium capsule of 0.7 mm internal and 0.8 mm external diameters. This work aims to evaluate the dosimetric paramet...

The aim of the present study was to construct the 125I-replication-selective oncolytic adenovirus (RSOAds)-human telomerase reverse transcriptase (hTERT)/prostate specific antigen (PSA) nuclide-oncolytic virus marker by labelling the hTERT/PSA double-regulation replicative oncolytic adenovirus with 125I nuclide, and investigate the influence of viral markers under various reaction conditions on...

Preincubation of Swiss 3T3 cells or human fibroblasts with purified platelet-derived growth factor (PDGF) at 4 degrees C or 37 degrees C rapidly inhibits subsequent binding of 125I-epidermal growth factor (125I-EGF). The effect does not result from competition by PDGF for binding to the EGF receptor since (a) very low concentrations of PDGF are effective, (b) cells with EGF receptors but no PDG...

To elucidate the role of the branched structure of sugar chains of human erythropoietin (EPO) in the expression of in vivo activity, the pharmacokinetic profile of a less active recombinant human EPO sample (EPO-bi) enriched with biantennary sugar chains was compared with that of a highly active control EPO sample enriched with tetraantennary sugar chains. After an intravenous injection in rats...

Basic fibroblast growth factor (bFGF) was radiolabeled and used in axonal transport studies to determine whether certain neuronal populations express functional receptors for bFGF. Unlike 125I-NGF, 125I-bFGF was not retrogradely transported in the adult rat sciatic nerve or from iris to trigeminal ganglion or superior cervical ganglion. However, after intraocular injection of 125I-bFGF into the...

We compared the specificities of transport mechanisms for uptake and efflux of thyroid hormones in cells of the human choriocarcinoma cell line, JAR, to determine whether triiodothyronine (T3), thyroxine (T4) and reverse T3 (rT3) are carried by the same transport mechanism. Uptake of 125I-T3, 125I-T4 and 125I-rT3 was saturable and stereospecific, but not specific for T3, T4 and rT3, as unlabell...

The nomenclature of the Adrenoceptors has been agreed by NC-IUPHAR Subcommittee on [64, 194]. Adrenoceptors, α1 three α1-adrenoceptor subtypes α1A, α1B and α1D are activated endogenous agonists (-)-adrenaline (-)-noradrenaline. -(-)phenylephrine, methoxamine cirazoline prazosin doxazosin antagonists considered selective for α1- relative to α2-adrenoceptors. [3H]prazosin [125I]HEAT (BE2254) rela...