Increased clearance explains lower plasma levels of tissue-type plasminogen activator by estradiol: Evidence for potently enhanced mannose receptor expression in mice

Several clinical studies have demonstrated an inverse relationship between circulating levels of estrogen and tissue-type plasminogen activator (t-PA). The present study was designed to test the hypothesis that estrogen lower plasma levels of t-PA by increasing its clearance from the bloodstream. 17α-Ethinyl estradiol (EE) treatment resulted in...

Effect of steroid hormones and retinoids on the formation of capillary-like tubular structures of human microvascular endothelial cells in fibrin matrices is related to urokinase expression

Angiogenesis, the formation of new capillary blood vessels, is a feature of a variety of pathological processes. To study the effects of a specific group of hormones (all ligands of the steroid/retinoid/thyroid hormone receptor superfamily) on the angiogenic process in humans, we have used a model system in which human microvascular endothelial...

Binding of human urokinase-type plasminogen activator to its receptor: Residues involved in species specificity and binding

Urokinase-type plasminogen activator (UPA), particularly when bound to its receptor (UPAR), is thought to play a major role in local proteolytic processes, thus facilitating cell migration as may occur during angiogenesis, neointima and atherosclerotic plaque formation, and tumor cell invasion. To facilitate understanding of the need and...

The effects of sex steroids on plasma levels of marker proteins of endothelial cell functioning

We studied thirteen male-to-female (M→F) and ten female-to-male (F→M) transsexuals who, for four months, received cross-sex treatment with, respectively, ethinylestradiol and cyproterone acetate, and with testosterone esters. We assessed the effects of treatment on plasma levels of tissue-type plasminogen activator (tPA), von Willebrand factor ...

Studies on the regulation of plasminogen activation-dependent processes by retinoids and steroid hormones

Cell-type specific DNA-protein interactions at the tissue-type plasminogen activator promoter in human endothelial and HeLa cells in vivo and in vitro

Tissue-type plasminogen activator (t-PA) gene expression in human endothelial cells and HeLa cells is stimulated by the protein kinase C activator phorbol 12-myristate 13-acetate (PMA) at the level of transcription. To study the mechanism of transcriptional regulation, we have characterized a segment of the t-PA gene extending from -135 to +100...

Effect of oral contraceptives on haemostasis variables

Combined oral contraceptives (COCs) have effects on a large number of haemostasis variables. We have summarised literature data on effects of COCs containing 30-35 μg ethinyl estradiol for the third generation of progestogens (PGs): desogestrel, gestodene and norgestimate. It is concluded that about 15 variables show a shift in distribution of...

Differences in metabolism and isomerization of all-trans-retinoic acid and 9-cis-retinoic acid between human endothelial cells and hepatocytes

Retinoic acid stimulates the expression of tissue-type plasminogen activator (t-PA) in vascular endothelial cells in vitro and enhances t-PA levels in plasma and tissues in vivo. Compared with the in vivo situation, high retinoic acid concentrations are required to induce optimally t-PA expression in vitro. These findings led us to study...

Stimulators of tissue-type plasminogen activator

Chemicals/CAS: 4 [2 (5,6,7,8 tetrahydro 5,5,8,8 tetramethyl 2 naphthyl) 1 propenyl]benzoic acid, 71441-28-6; butyric acid, 107-92-6, 156-54-7, 461-55-2; cyclic AMP, 60-92-4; protein kinase C, 141436-78-4; retinoic acid, 302-79-4; tissue plasminogen activator, 105913-11-9; trichostatin A, 58880-19-6

Rapid metabolism of retinoic acid by cultured human vascular endothelial cells as compared to the human hepatoma cell line HepG2

Chemicals/CAS: cytochrome P450, 9035-51-2; retinoic acid, 302-79-4

Effects of steroid hormones on the secretion of hemostatic factors in, and angiogenic properties of, human vascular endothelial cells

Regulation of t-pa expression by retinoic acid in cultured human endothelial cells in vitro and in rats in vivo

We and others have previously shown that retinoids (vitamin A derivatives) regulate t-PA synthesis in human endothelial cells in vitro and in rats in vivo. Retinoids exert their effect on t-PA expression via specific nuclear receptors, retinoic acid receptors (RARs). of which several subtypes and isoforms exist. Using subtype-specific retinoids...

Stimulation of tissue-type plasminogen activator expression by retinoic acid in human endothelial cells requires retinoic acid receptor β2 induction

We previously showed the involvement of retinoic acid receptor α (RARα) in the induction of tissue-type plasminogen activator (t-PA) synthesis by RA in human umbilical vein endothelial cells (HUVECs). However, the rather slow onset of this induction of t-PA synthesis suggested an indirect role of RARα. Here, we show that the protein synthesis...