We evaluated the potencies of radioiodinated (-)-o-iodovesamicol [(-)-oIV] as a selective vesicular acetylcholine transporter (VAChT) mapping agent. (-)-[125I]oIV exhibited significant accumulation (about 2.8% of the injected dose) in rat brain. The regional brain distribution of radioactivity was similar for both (-)-[125I]olV and (-)-[3H]vesamicol. The accumulation of (-)-[125I]oIV in the bra...

The plasma clearance kinetics of the amyloid-related high density lipoprotein (HDL) apoprotein serum amyloid protein (apoSAA) was examined in BALB/c mice by two different methods, using labeled 125I-apoSAA-rich HDL and unlabeled plasma apoSAA (clearance monitored by radioimmunoassay). The plasma half-life of apoSAA, estimated by both methods, was on the order of 75-80 min, as compared with a va...

The catabolism of streptokinase (SK) and polyethylene glycol derivatives of SK (PEG-SK) were studied in mice. The clearance and catabolism of SK:plasmin (SK:Pm) and PEG-SK:Pm activator complexes were also investigated. Native 125I-SK cleared rapidly (t1/2 = 15 minutes) from the circulation, with the majority of the ligand accumulating in the liver and gastrointestinal (GI) tract and a substanti...

UNLABELLED We expressed the high affinity nerve growth factor receptor TrkA in Chinese hamster ovary (CHO) fibroblasts to study nerve growth factor (NGF) trafficking and processing events following receptor-mediated ligand internalization in a nonneuronal and p75 minus cell line. These stable clonal cell lines express approximately 2.5 x 10(5) TrkA receptors and bind 125I-NGF with high affinity...

125I-labelled heat-labile toxin (from Escherichia coli) and 125I-labelled cholera toxin bound to immobilized ganglioside GM1 and Balb/c 3T3 cell membranes with identical specificities, i.e. each toxin inhibited binding of the other. Binding of both toxins to Balb/c 3T3 cell membranes was saturable, with 50% of maximal binding occurring at 0.3 nM for cholera toxin and 1.1 nM for heat-labile toxi...

We have examined the uptake and distribution of 125I-labeled human high density lipoprotein, apolipoprotein E-free (hHDL3), 125I-rat high density lipoprotein (HDL), and human HDL (hHDL) reconstituted with [3H]cholesteryl linoleate after their in situ vascular perfusion to ovaries of gonadotropin-primed immature rats on days 6-9 post human chorionic gonadotropin (hCG)-injection. Some rats were t...

OBJECTIVES It has been postulated that radiopharmaceuticals can be used to predict the therapeutic response to (chemo)therapy, which could lead to individualized treatment regimens. In this study, 18F-deoxyglucose, 99mTc-tetrofosmin, 125I-deoxyuridineribose, and 125I-methyltyrosine were tested for this purpose. METHODS The uterine sarcoma cell line MES-SA (MDR-) and its multidrug resistant va...

The objective of the present study is to test daily and seasonal changes in 2-[125I]-Melatonin ([125I]-Mel) binding in different brain areas and the retina of the frog Rana perezi as well as the possible effect of light and temperature on melatonin receptors. During the day-night cycle, binding of [125I]-Mel showed a clear rhythm in the optic tectum, diencephalon, telencephalon, and neural reti...

A monoclonal antibody (MAb) 8 [immunoglobulin G3 (IgG3)], directed against a Mr 48,000 human lung cancer-associated antigen, was radiolabeled with either 125I or 131I, and its biodistribution was studied in nude mice bearing human lung cancer (TKB-2) over a 7-day period. 125I-labeled MAb 8 increased its binding to the tumor during the period, while the binding of 125I-labeled control IgG3 decli...

Receptor-mediated endocytosis of tissue-type plasminogen activator (t-PA)-plasminogen activator inhibitor type 1 (PAI-1) complexes results in their clearance by Hep G2 cells. After complexes are internalized, the t-PA component is degraded. However, neither the locus of intracellular catabolism nor the fate of PAI-1 has been elucidated. To characterize these aspects of t-PA-PAI-1 catabolism, th...