Phospholipases dependence

Kelly RB, von Wedel RJ, Strong PN (1979) Phospholipase-dependent and phospholipase-independent inhibition of transmitter relase by beta-bungarotoxin. Adv Cytopharmacol 3 77-85 Kerner (1817) Vergiftung durch verborbene Wurste. Tubinger Blatter 3 1-25 Kielian M, Rey FA (2006) Virus membrane-fusion proteins more than one way to make a hairpin. Nat Rev Microbiol 4 67-76... 

TBT and TFT are membrane-active molecules, and their mechanism of action appears to be strongly dependent on organotin(IV) lipophilicity. They function as ionophores and produce hemolysis, release Ca(II) from sarcoplasmic reticulum, alter phosphatodylseiine-induced histamine release, alter mitochondrial membrane permeability and perturb membrane enzymes. Organotin(IV) compounds have been shown to affect cell signaling they activate protein kinase and increase free arachidonic acid through the activation of phospholipase... 

Figure 1. Simplified schematic of receptor-mediated signal transduction in neutrophils. Binding of ligand to the receptor activates a guanine-nucleotide-binding protein (G protein), which then stimulates phospholipase C. Phosphatidylinositol 4,5-bis-phosphate is cleaved to produce diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3). DAG stimulates protein kinase C. IP3 causes the release of Ca from intracellular stores, which results in an increase in the cytosolic Ca concentration. This increase in Ca may stimulate protein kinase C, calmodulin-dependent protein kinases, and phospholipase A2. Protein phosphorylation events are thought to be important in stimulating degranulation and oxidant production. In addition, ionic fluxes occur across the plasma membrane. It is possible that phospholipase A2 and ionic channels may be governed by G protein interactions. ...

Cellular lipoxygenases have been implicated as possible enzymatic mediators of endothelial cell-dependent oxidation of LDL. Inhibitors of lipoxygenase, but not cyclooxygenase, have been shown to be effective inhibitors of LDL oxidation using rabbit endothelial cells (Parthasarathy etal., 1989). Interestingly, a phospholipase A2 activity intrinsic to apo-B has also been implicated in the endothelial cell-dependent modification of LDL (Parthasarathay et al., 1985). 

CotteriU, L.A., Gower, J.D., FuUer, B.J. and Green, C.J. (1989c). Free fatty acid accumulation foUowingcold ischaemia in rabbit kidneys and the involvement of a calcium dependent phospholipase A2. Cryolett. 11, 3-12. 

Smit MJ, Verdijk P, van der Raaij-Helmer EM, et al. CXCR3-mediated chemotaxis of human T cells is regulated by a Gi- and phospholipase C-dependent pathway and not via activation of MEK/p44/p42 MAPK nor Akt/PI-3 kinase. Blood 2003 102(6) 1959-1965. 

Cronshaw DG, Kouroumalis A, Parry R, Webb A, Brown Z, Ward SG. Evidence that phospholipase C-dependent, calcium-independent mechanisms are required for directional migration of T lymphocytes in response to the CCR4 ligands CCL17 and CCL22. J Leukoc Biol 2006 79(6) 1369-1380. 

A. indica L. Indian Aristolochia, also known as Indian birthwort, ishvara (Sanskrit), or adagam (Tamil), is a bitter climber native to India. The medicinal material consists of the rhizome, which is to resolve inflammation (India), counteract insect poison, and as an antipyretic (Philippines and Vietnam). The rhizome contains aristolochic acid, which inhibits in vitro and dose-dependent phospholipid hydrolysis by the human synovial fluid phospholipase A2, snake venom phospholipase A2, porcine pancreatic phospholipase A2, and human platelet phospholipase A2 (2). 

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