The expression of surface procoagulants by exudative macrophages represents an important mechanism underlying local fibrin deposition at sites of extravascular inflammation. The present studies investigated the contribution of tyrosine phosphorylation to the generation of macrophage procoagulant activity (PCA) and tissue factor expression in response to proinflammatory stimuli. Both lipopolysac...

Insulin regulates the expression of genes involved in a variety of metabolic processes. In chick-embryo hepatocytes in culture, insulin amplifies the tri-iodothyronine (T3)-induced enzyme activity, and the level and rate of transcription of mRNA for both fatty acid synthase (FAS) and malic enzyme (ME). Insulin alone, however, has little or no effect on the expression of these genes. In chick-em...

Skeletal mass is maintained by a balance between formation and resorption, cell proliferation and apoptosis. In vitro, glucocorticoids (GCs) decrease extracellular signal-regulated kinases (ERK) activation by mitogens, thus inhibiting osteoblast proliferation. Both ERK activity and proliferation are restored by co-treatment with the protein tyrosine phosphatase inhibitor, vanadate. Since ERK si...

The potential roles of protein tyrosine kinases (TKs) and of phosphotyrosine phosphatases (PTPs) in pancreatic islet function are not known. In this study, we investigated whether vanadate, a potent PTP inhibitor, affects phosphoinositide (PI) metabolism by a TK-dependent pathway in isolated mouse islets. To avoid the confounding effects of changes in Ca2+ influx, all experiments were performed...

Mitotic PtK1 cells, lysed at anaphase into a carbowax 20 M Brij 58 solution, continue to move chromosomes toward the spindle poles and to move the spindle poles apart at 50% in vivo rates for 10 min. Chromosome movements can be blocked by adding metabolic inhibitors to the lysis medium and inhibition of movement can be reversed by adding ATP to the medium. Vanadate at micromolar levels reversib...

In this study we have explored whether the bifunctional protein semicarbazide-sensitive amine oxidase (SSAO)/vascular adhesion protein-1 (VAP-1) represents a novel target for type 2 diabetes. To this end, Goto-Kakizaki (GK) diabetic rats were treated with the SSAO substrate benzylamine and with low ineffective doses of vanadate previously shown to have antidiabetic effects in streptozotocin-ind...

The maltose transport system in Escherichia coli is a member of the ATP-binding cassette superfamily of transporters that is defined by the presence of two nucleotide-binding domains or subunits and two transmembrane regions. The bacterial import systems are unique in that they require a periplasmic substrate-binding protein to stimulate the ATPase activity of the transport complex and initiate...

Administration of vanadate, an insulinomimetic agent, has been shown to normalize the increased number of insulin receptors in the liver of streptozotocin-induced diabetic rats. In the present study, the effects of vanadate on various steps of expression of the liver insulin receptor gene in diabetic rats have been analyzed and compared with those of phlorizin, a glucopenic drug devoid of insul...

The vanadate cofactor in vanadium chloroperoxidase has been studied using UV-VIS absorption spectroscopy. A band is present in the near-UV that is red-shifted as compared to free vanadate and shifts in both position and intensity upon change in pH. Mutation of vanadate binding residues has a clear effect on the spectrum. Substrate-induced spectral effects allow direct measurement of separate ki...

The effect of vanadate on the ATP-induced disruption of trypsin-treated axonemes and the ATP-induced straightening of rigor wave preparations of sea urchin sperm was investigated. Addition of ATP to a suspension of trypsin-treated axonemes results in a rapid decrease in turbidity (optical density measured at 350 nm) concomitant with the disruption of the axonemes by sliding between microtubules...