PGH2, Endoperoxide H2, Prostaglandin R2
3D model (JSmol)
CompTox Dashboard (EPA)
|Molar mass||352.465 g/mol|
|Density||1.129 ± 0.06 g/mL|
|Boiling point||490 ± 40.0 °C|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|what is ?)(|
Prostaglandin H2 is a type of prostaglandin and a precursor for many other biologically significant molecules. It is synthesized from arachidonic acid in a reaction catalyzed by a cyclooxygenase enzyme. The conversion from Arachidonic acid to Prostaglandin H2 is a two step process. First, COX-1 catalyzes the addition of two free oxygens to form the 1,2-Dioxane bridge and a peroxide functional group to form Prostaglandin G2. Second, COX-2 reduces the peroxide functional group to a Secondary alcohol, forming Prostaglandin H2. Other peroxidases like Hydroquinone have been observed to reduce PGG2 to PGH2. PGH2 is unstable at room temperature, with a half life of 90-100 seconds, so it is often converted into a different prostaglandin.
It is acted upon by:
- Prostacyclin synthase to create prostacyclin
- Thromboxane-A synthase to create thromboxane A2 and 12-(S)-hydroxy-5Z,8E,10E-heptadecatrienoic acid (HHT) (see 12-Hydroxyheptadecatrienoic acid)
- Prostaglandin D2 synthase to create prostaglandin D2
- Prostaglandin E synthase to create prostaglandin E2
It rearranges non-enzymatically to:
- A mixture of 12-(S)-hydroxy-5Z,8E,10E-heptadecatrienoic acid (HHT) and 12-(S)-hydroxy-5Z,8Z,10E-heptadecatrienoic acid (see 12-Hydroxyheptadecatrienoic acid)
Use of prostaglandin H2:
- regulating the constriction and dilation of blood vessels
- stimulating platelet aggregation
Effects of Aspirin on prostaglandin H2:
- Aspirin has been hypothesized to block the conversion of arachidonic acid to prostaglandin
- Wishart, David S.; Djombou Feunang, Yannick; Marcu, Ana; Guo, An Chi; Liang, Kevin; Vázquez Fresno, Rosa; Sajed, Tanvir; Johnson, Daniel; Li, Carin; Karu, Naama; Sayeeda, Zinat; Lo, Elvis; Assempour, Nazanin; Berjanskii, Mark; Singhal, Sandeep; Arndt, David; Liang, Yonjie; Badran, Hasan; Grant, Jason; Serra Cayuela, Arnau; Liu, Yifeng; Mandal, Rupa; Neveu, Vanessa; Pon, Allison; Knox, Craig; Wilson, Michael; Manach, Claudine; Scalbert, Augustin. "Showing metabocard for Prostaglandin H2 (HMDB0001381)". Human Metabolome Database, HMDB. 4.0.
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