• APC improved adenosine triphosphate recovery in young rats but not in aged rats. (asahq.org)
  • 6,7 The mechanism of volatile anesthetic preconditioning (APC), although not fully understood, is believed to share similarities with IPC by activation of adenosine triphosphate (ATP)-sensitive potassium (K ATP ) channels, particularly in the mitochondria. (asahq.org)
  • Variously substituted 7-deazaguanines are of interest as inhibitors of GTP cyclohydrolase I, the first enzyme in the biosynthetic pathway leading to dihydrofolate and tetrahydrobiopterin. (strath.ac.uk)
  • In enzymology, a GTP cyclohydrolase II (EC 3.5.4.25) is an enzyme that catalyzes the chemical reaction GTP + 3 H2O ⇌ {\displaystyle \rightleftharpoons } formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine + diphosphate Thus, the two substrates of this enzyme are GTP and H2O, whereas its 3 products are formate, 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine, and diphosphate. (wikipedia.org)
  • We have now investigated the importance and mechanisms of BH4 availability in vivo using a novel transgenic mouse model with endothelial-targeted overexpression of the rate-limiting enzyme in BH4 synthesis, guanosine triphosphate-cyclohydrolase I (GTPCH). (ox.ac.uk)
  • This current study investigates mutations in the gene guanosine triphosphate cyclohydrolase-1 (GCH1), an essential enzyme for dopamine production in nigrostriatal cells. (health-innovations.org)
  • Resveratrol downregulates the expression and activity of the oxidase inhibiting NADPH oxidase-mediated production of reactive oxygen species (ROS), stimulates mitochondria biogenesis reducing mitochondrial superoxide generation and upregulates the tetrahydrobiopterin-synthesizing enzyme guanosine triphosphate (GTP) cyclohydrolase I preventing superoxide production from uncoupled endothelial nitric oxide synthase. (encyclopedia.pub)
  • Results show that on average Caucasians with one bad version of a gene known as guanosine triphosphate cyclohydrolase-1, or GCH1, developed Parkinson's symptoms five years earlier, and had a 23% increased risk for the disease. (health-innovations.org)
  • For a complete list of articles on Guanosine Triphosphate Cyclohydrolase I Deficiency (GTPCH) please refer to the Online Mendelian Inheritance in Man (OMIM) which is linked below. (pndassoc.org)
  • With regard to BH4 deficiencies, more than 190 different mutant alleles or molecular lesions have been identified, including in the genes for guanosine triphosphate cyclohydrolase (GCH), 6-pyruvoyl-tetrahydropterin synthase (PTPS), sepiapterin reductase (SR), carbinolamine-4a-dehydratase (PCD), and dihydropteridine reductase (DHPR). (medscape.com)
  • Polymorphisms of Nav1.6 sodium channel, Brain-derived Neurotrophic Factor, Catechol-O-methyltransferase and Guanosine Triphosphate Cyclohydrolase 1 genes in trigeminal neuralgia. (cdc.gov)
  • No correlation was found between 4-HNE accumulation and the expression of the antioxidant enzymes glutathione peroxidase 4, ferroptosis suppressor protein 1, and guanosine triphosphate cyclohydrolase 1. (bvsalud.org)
  • Xanthylic acid is an important metabolic intermediate in the purine metabolism, and is a product or substrate of the enzymes inosine monophosphate dehydrogenase (EC 1.1.1.205), hypoxanthine phosphoribosyltransferase (EC 2.4.2.8), xanthine phosphoribosyltransferase (EC 2.4.2.22), 5'-ribonucleotide phosphohydrolase (EC 3.1.3.5), Ap4A hydrolase (EC 3.6.1.17), nucleoside-triphosphate diphosphatase (EC 3.6.1.19), phosphoribosylamine-glycine ligase (EC 6.3.4.1), and glutamine amidotransferase (EC 6.3.5.2). (ecmdb.ca)
  • Tetrahydrobiopterin-dependent preservation of nitric oxide-mediated endothelial function in diabetes by targeted transgenic GTP-cyclohydrolase I overexpression. (ox.ac.uk)
  • GTP - (= guanosine 5 triphosphate) Like ATP a source of phosphorylating potential, but is separately synthesized and takes part in a limited, distinct set of energy requiring processes. (fr-academic.com)
  • Role of nitric oxide on purinergic signalling in the cochlea Harada, Narinobu 2010-06-08 00:00:00 In the inner ear, there is considerable evidence that extracellular adenosine 5′-triphosphate (ATP) plays an important role in auditory neurotransmission as a neurotransmitter or a neuromodulator, although the potential role of adenosine signalling in the modulation of auditory neurotransmission has also been reported. (sagepub.com)
  • Autosomal dominant guanosine triphosphate cyclohydrolase I (GCH-I) deficiency (Segawa disease) is a dopa-responsive dystonia caused by mutation of the GCH-I gene located on 14q22.1-q22.2. (nih.gov)
  • Hyperphenylalaninemia (HPA) is the first diagnostic hallmark for most BH 4 deficiencies, apart from autosomal dominant guanosine triphosphate cyclohydrolase I deficiency and sepiapterin reductase deficiency. (wustl.edu)
  • 4. Cell-autonomous role of endothelial GTP cyclohydrolase 1 and tetrahydrobiopterin in blood pressure regulation. (nih.gov)
  • 8. Gene transfer of human guanosine 5'-triphosphate cyclohydrolase I restores vascular tetrahydrobiopterin level and endothelial function in low renin hypertension. (nih.gov)
  • 12. HMG-CoA reductase inhibitor increases GTP cyclohydrolase I mRNA and tetrahydrobiopterin in vascular endothelial cells. (nih.gov)
  • 13. Quantitative regulation of intracellular endothelial nitric-oxide synthase (eNOS) coupling by both tetrahydrobiopterin-eNOS stoichiometry and biopterin redox status: insights from cells with tet-regulated GTP cyclohydrolase I expression. (nih.gov)
  • 16. Hydrogen peroxide stimulates tetrahydrobiopterin synthesis through the induction of GTP-cyclohydrolase I and increases nitric oxide synthase activity in vascular endothelial cells. (nih.gov)
  • 17. GTP cyclohydrolase I gene transfer augments intracellular tetrahydrobiopterin in human endothelial cells: effects on nitric oxide synthase activity, protein levels and dimerisation. (nih.gov)
  • 18. Apolipoprotein A-I mimetic peptide inhibits atherosclerosis by increasing tetrahydrobiopterin via regulation of GTP-cyclohydrolase 1 and reducing uncoupled endothelial nitric oxide synthase activity. (nih.gov)
  • Without enough GTP cyclohydrolase 1, little or no tetrahydrobiopterin is produced. (medlineplus.gov)
  • PPAR-α Agonist Fenofibrate Upregulates Tetrahydrobiopterin Level through Increasing the Expression of Guanosine 5′-Triphosphate Cyclohydrolase-I in Human Umbilical Vein Endothelial. (uitm.edu.my)
  • A reduction in functional GTP cyclohydrolase 1 enzyme causes less dopamine and serotonin to be produced, leading to the movement problems and other characteristic features of dopa-responsive dystonia. (medlineplus.gov)
  • GTP cyclohydrolase 1-deficient dopa-responsive dystonia (GTPCH1-deficient DRD) is characterized by childhood-onset dystonia and a dramatic and sustained response to low doses of oral administration of levodopa. (nih.gov)
  • In enzymology, a GTP cyclohydrolase II (EC 3.5.4.25) is an enzyme that catalyzes the chemical reaction GTP + 3 H2O ⇌ {\displaystyle \rightleftharpoons } formate + 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine + diphosphate Thus, the two substrates of this enzyme are GTP and H2O, whereas its 3 products are formate, 2,5-diamino-6-hydroxy-4-(5-phosphoribosylamino)pyrimidine, and diphosphate. (wikipedia.org)
  • EC 3.5.4.16 ( GTP cyclohydrolase I) and EC 3.5.4.25 ( GTP cyclohydrolase II). (nih.gov)
  • Researchers believe that the abnormal enzyme may interfere with the activity of the normal version of GTP cyclohydrolase 1 that is produced from the copy of the gene with no mutation. (medlineplus.gov)
  • Polymorphic variation of the guanosine triphosphate cyclohydrolase 1 gene predicts outcome in patients undergoing surgical treatment for lumbar degenerative disc disease. (cdc.gov)
  • Association of guanosine triphosphate cyclohydrolase 1 gene polymorphisms with fibromyalgia syndrome in a Korean population. (cdc.gov)
  • Additionally, a reduction in GTP cyclohydrolase 1 activity disrupts the production of certain neurotransmitters in the brain. (medlineplus.gov)
  • Furthermore, we demonstrate that RNAi knockdown of α-syn results in a nearly twofold increase in GTP cyclohydrolase I activity and a concomitant increase in basal BH4 levels. (ox.ac.uk)