Thromboxane-A synthase
Encyclopedia
Thromboxane A synthase 1 (platelet, cytochrome P450, family 5, subfamily A), also known as TBXAS1, is an enzyme
that, in humans, is encoded by the TBXAS1 gene
.
proteins are monooxygenases that catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids, and other lipids. However, this protein is considered a member of the cytochrome P450 superfamily on the basis of sequence similarity rather than functional similarity. This endoplasmic reticulum membrane protein catalyzes the conversion of prostaglandin H2
to thromboxane A2
, a potent vasoconstrictor and inducer of platelet aggregation. The enzyme plays a role in several pathophysiological processes including hemostasis, cardiovascular disease, and stroke. The gene expresses two transcript variants.
s. Ifetroban
is a potent and selective thromboxane receptor antagonist. Dipyridamole
antagonizes this receptor too, but has various other mechanisms of antiplatelet activity as well. Picotamide
has activity both as a thromboxane synthase inhibitor and as a thromboxane receptor antagonist.
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
that, in humans, is encoded by the TBXAS1 gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
.
Function
This gene encodes a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450Cytochrome P450 oxidase
The cytochrome P450 superfamily is a large and diverse group of enzymes. The function of most CYP enzymes is to catalyze the oxidation of organic substances. The substrates of CYP enzymes include metabolic intermediates such as lipids and steroidal hormones, as well as xenobiotic substances...
proteins are monooxygenases that catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids, and other lipids. However, this protein is considered a member of the cytochrome P450 superfamily on the basis of sequence similarity rather than functional similarity. This endoplasmic reticulum membrane protein catalyzes the conversion of prostaglandin H2
Prostaglandin H2
Prostaglandin H2 is a type of Prostaglandin which is derived from arachidonic acid and is a precursor for many other biologically significant molecules.It is acted upon by:* prostacyclin synthase to create prostacyclin...
to thromboxane A2
Thromboxane A2
Thromboxane A2 is a thromboxane. It is produced by activated platelets and has prothrombotic properties: it stimulates activation of new platelets as well as increases platelet aggregation. This is achieved by mediating expression of the glycoprotein complex GP IIb/IIIa in the cell membrane of...
, a potent vasoconstrictor and inducer of platelet aggregation. The enzyme plays a role in several pathophysiological processes including hemostasis, cardiovascular disease, and stroke. The gene expresses two transcript variants.
Inhibitors
are used as antiplatelet drugAntiplatelet drug
An antiplatelet drug is a member of a class of pharmaceuticals that decrease platelet aggregation and inhibit thrombus formation...
s. Ifetroban
Ifetroban
Ifetroban is a potent and selective thromboxane receptor antagonist....
is a potent and selective thromboxane receptor antagonist. Dipyridamole
Dipyridamole
Dipyridamole is a drug that inhibits thrombus formation when given chronically and causes vasodilation when given at high doses over a short time.-Mechanism and effects:...
antagonizes this receptor too, but has various other mechanisms of antiplatelet activity as well. Picotamide
Picotamide
Picotamide is a platelet aggregation inhibitor. It works as a thromboxane synthase inhibitor and a thromboxane receptor inhibitor, the latter by modifying cellular responses to activation of the thromboxane receptor....
has activity both as a thromboxane synthase inhibitor and as a thromboxane receptor antagonist.