background: uterine natural killer (unk) cells are the most abundant leukocytes in pre-implantation endometrium and early pregnancy deciduas in humans and rodents. they are associated with structural changes in maternal spiral arteries but regulation of their re-cruitment and activation is incompletely understood. the major subpopulation of unk cells in humans expresses cd56, the neural cell ad...

BACKGROUND The production of collagen is fundamental to atherosclerosis and critically dependent on posttranslational modification by prolyl 4-hydroxylase. METHODS AND RESULTS We report the cloning of a novel prolyl 4-hydroxylase catalytic (alpha) subunit from human vascular smooth muscle cells. The peptide displayed conservation of critical residues for interacting with Fe2+ and 2-oxoglutara...

Phenylalanine hydroxylase was shown to be inhibited by oudenone and its derivatives in vitro. At a concentration of 2.3 x 10(-3) M, oudenone inhibited phenylalanine hydroxylase by 50%, and some of the oudenone derivatives showed more potent inhibition. The kinetic data have shown that the inhibition by oudenone is competitive with a tetrahydropterin cofactor (6,7-dimethyltetrahydropterin, DMPH4...

The conversion of vitamin D into an active ligand for the vitamin D receptor requires 25-hydroxylation in the liver and 1alpha-hydroxylation in the kidney. Mitochondrial and microsomal vitamin D 25-hydroxylase enzymes catalyze the first reaction. The mitochondrial activity is associated with sterol 27-hydroxylase, a cytochrome P450 (CYP27A1); however, the identity of the microsomal enzyme has r...

According to the present paradigm, 1alpha,25-dihydroxyvitamin D3 [1alpha,25-(OH)2D3] is a biologically active hormone; whereas 25-hydroxyvitamin D3 (25OHD3) is regarded as a prohormone activated through the action of 25-hydroxyvitamin D3 1alpha-hydroxylase (1alpha-hydroxylase). Although the role of vitamin D3 in the regulation of growth and differentiation of prostatic epithelial cells has been...

A sensitive method was developed for determining the phenylalanine hydroxylase activity of crude tissue preparations in the presence of optimum concentrations of the 6,7-dimethyl-5,6,7,8-tetrahydropterin cofactor (with ascorbate or dithiothreitol to maintain its reduced state) and substrate. Tissue distribution studies showed that, in addition to the liver, the kidney also contains significant ...

Fibrates are hypolipidemic drugs that affect the expression of genes involved in lipid metabolism by activating peroxisome proliferator–activated receptors (PPARs). Fibrate treatment causes adverse changes in biliary lipid composition and decreases bile acid excretion, leading to an increased incidence of cholesterol gallstones. In this study, we investigated the effect of fibrates on bile acid...

It has been reported that the administration of cycloheximide, a protein synthesis inhibitor, depresses brain tyrosine hydroxylase activity as measured in vitro. This finding raised the possibility that the amnesic effect of this drug could be due to reduction of norepinephrine synthesis rather than to inhibition of protein synthesis required for long-term memory. We have found that (1) amnesic...

Tyrosine hydroxylase is synthesized de nouo in rat superior cervical ganglia in organ culture. The differential rate of synthesis is not increased significantly by the addition of nerve growth factor to the culture. Prior administration of nerve growth factor in vim. however, leads to an augmented synthesis of tyrosine hydroxylase in ganglia subsequently cultured in vitro. The differential rate...