(1R,4aR,4bS,7R,10aR)-7-Ethenyl-1,4a,7-trimethyl-3,4,4b,5,6,9,10, 10a-octahydro-2H-phenanthrene-1-carboxylic acid
3D model (Jmol)
|Molar mass||302.46 g·mol−1|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|what is ?)(|
IPA originates from many sorts of trees, especially conifers.
Mode of action
BK channels are formed by α subunits and accessory β subunits arranged in tetramers. The α subunit forms the ion conduction pore and the β subunit contributes to channel gating. IPA interaction with the BK channel enhances Ca2+ and / or voltage sensitivity of the α subunit of BK channels without affecting the channel conductance. In this state BK channels can still be inhibited by one of their inhibitors, like charybdotoxin (CTX). Opening of the BK channel leads to an increased K+-efflux which hyperpolarizes the resting membrane potential, reducing the excitability of the cell in which the BK-channel is expressed.
Studies on rainbow trout hepatocytes have shown that IPA increases intracellular calcium release, leading to a disturbance in the calcium homeostasis. This could be important in the possible toxicity of the toxin.
This toxin may be of value in the treatment of urinary bladder overactivity, stroke treatment and in problems with the hyperactivity of (vascular) smooth muscle cells.
- Wilson, AE; Moore, ER; Mohn, WW (1996). "Isolation and characterization of isopimaric acid-degrading bacteria from a sequencing batch reactor". Applied and Environmental Microbiology. 62 (9): 3146–51. PMC . PMID 8795202.
- Hwang, J. S. (1996). Modern solder technology for competitive electronics manufacturing. Electronic packaging and interconnection series McGraw-Hill
- Kaczorowski, GJ; Knaus, HG; Leonard, RJ; McManus, OB; Garcia, ML (1996). "High-conductance calcium-activated potassium channels; structure, pharmacology, and function". Journal of bioenergetics and biomembranes. 28 (3): 255–67. doi:10.1007/bf02110699. PMID 8807400.
- Imaizumi, Y; Sakamoto, K; Yamada, A; Hotta, A; Ohya, S; Muraki, K; Uchiyama, M; Ohwada, T (2002). "Molecular basis of pimarane compounds as novel activators of large-conductance Ca(2+)-activated K(+) channel alpha-subunit". Molecular Pharmacology. 62 (4): 836–46. doi:10.1124/mol.62.4.836. PMID 12237330.
- Råbergh, Christina M.I.; Lilius, Henrik; Eriksson, John E.; Isomaa, Boris (1999). "The resin acids dehydroabietic acid and isopimaric acid release calcium from intracellular stores in rainbow trout hepatocytes". Aquatic Toxicology. 46: 55–65. doi:10.1016/S0166-445X(98)00115-5.
- Råbergh, C.M.I.; Isomaa, B.; Eriksson, J.E. (1992). "The resin acids dehydroabietic acid and isopimaric acid inhibit bile acid uptake and perturb potassium transport in isolated hepatocvtes from rainbow trout (Oncorhynchus mykiss)". Aquatic Toxicology. 23 (3–4): 169–179. doi:10.1016/0166-445X(92)90050-W.