Transformation of TXA2 to TXB2
Thromboxane A2 is a bioactive molecule which affects vasoactivity and promotes thrombosis. It is unstable due to the epoxide functional group, and as a consequence has a short half-life of 20- 30 seconds. The hydrolysis reaction results in the generation of biologically inactive TXB2.
Contents
Reaction
Chemical equation
Rate equation
Parameters
| Value | Units | Conditions | Substrate | Reference |
|---|---|---|---|---|
| 3.7e3 ± 0.1e3 | M-1 s-1 | NaCl04 (0.1 - 0.2 M)
Temperature: 25°C |
3 | [1] |
| 8.7e3 | M-1 s-1 | KCl (1 M)
Temperature: 25°C |
3 | [1] |
| 1.1e4 ± 0.1e4 | M-1 s-1 | NaCl04 (0.1 - 0.2 M)
Temperature: 25°C |
4 | [1] |
| 2.4 e4 | M-1 s-1 | KCl (1M)
Temperature: 25°C |
4 | [1] |
| 3.7e3 ± 0.1e3 | M-1 s-1 | NaCl04 (0.1 - 0.2 M)
Temperature: 25°C |
5 | [1] |
| 3.6 ± 0.2 | M-1 s-1 | NaCl04 (0.1 - 0.2 M)
Temperature: 25°C |
6 | [1] |
| 1.7 ± 0.1 | M-1 s-1 | NaCl04 (0.1 - 0.2 M)
Temperature: 25°C |
7 | [1] |
| 26.7 ± 0.9 | M-1 s-1 | NaCl04 (0.1 - 0.2 M)
Temperature: 25°C |
8 | [1] |
| 35 | M-1 s-1 | KCl (1M)
Temperature: 25°C |
8 | [1] |
| Value | Units | Conditions | Substrate | Reference |
|---|---|---|---|---|
| Value | Units | Conditions | Substrate | Reference |
|---|---|---|---|---|
| 0.000038 | mM | Temperature: 35°C
Vector:Mosquito Note: "In solution, it undergoes rapid hydrolysis to form TXB2, a stable but physiologically inactive compound." - therefore they used stable analogues. |
carbocyclic TXA2 (analogue of TXA2) | [2] |
| 0.00000023 | mM | Temperature: 35°C
Vector:Rabbit cultured astrocytes Note: "In solution, it undergoes rapid hydrolysis to form TXB2, a stable but physiologically inactive compound." - therefore they used stable analogues. |
[3H]IONO NT-126, a TXA z antagonist, | [3] |
| 1500 ± 500 | mM | Temperature: 25°C
In vitro |
Hydroxysulfamic acid
 |
[4] |
 |
N/A | H2O2 | Temperature: 20°C
In vitro |
[4] |
Related Reactions
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 A. Ross "Vinyl epoxide hydrolysis reactions" J. Am. Chem. Soc., 1982, 104 (6), pp 1658–1665
- ↑ P. H. Alvarenga "The Function and Three-Dimensional Structure of a Thromboxane A2/Cysteinyl Leukotriene-Binding Protein from the Saliva of a Mosquito Vector of the Malaria Parasite" PLoS Biol. 2010 Nov 30;8(11):e1000547. doi: 10.1371/journal.pbio.1000547.
- ↑ N Nakahata et al. "The Presence of Thromboxane A2 Receptors in Cultured Astrocytes From Rabbit Brain" Brain Res 583 (1-2), 100-104. 1992 Jun 26
- ↑ 4.0 4.1 D. LITTLEJOHN "The dissociation constant and acid hydrolysis rate of hydroxysulfamic acid" Can. J. Chem. 67, 1596 (1989). Cite error: Invalid
<ref>tag; name "Littlejohn1989.E2.80.9D" defined multiple times with different content
