Calcium flux

Flubendiamide is an example of a new chemical class of insecticides that have been termed phthalic acid diamides (Nauen 2006, Copping and Duke 2007). They are related to the alkaloid ryanodine, which is extracted from Ryania species. Ryanodine affects muscles by binding to calcium channels of the sarcoplasmic reticulum. Ca + ions act as intracellular messengers, and their flux is modulated by calcium channels of this type. The toxic action of ryanodine and synthetic insecticides related to it is due to the disturbance of calcium flux. 

Deiva K, Geeraerts T, Salim H, Leclerc P, Hery C, Hugel B, Freyssinet JM, Tardieu M (2004) Fractalkine reduces N-methyl-d-aspartate-induced calcium flux and apoptosis in human neurons through extracellular signal-regulated kinase activation. Eur J Neurosci 20(12) ... 

The opiate receptors in the spinal cord are predominantly of the mu and delta type and are found in the C-fibre terminal zone (the substantia gelatinosa) in the superficial dorsal horn. Considerable numbers of ORL-1 receptors are also found in this area. Up to 75% of the opiate receptors are found presynaptically on the C-fibre terminals and when activated inhibit neurotransmitter release. The opening of potassium channels will reduce calcium flux in the terminal and so there will be a resultant decrease in... 

CCR1 is a promiscuous chemokine receptor bound by several chemokines, such as MIP-la/CCL3, MIP-lp/CCL4, and RANTES/CCL5 (25-28). Although these chemokines are generally known to attract monocytes but not neutrophils in vitro (29), a previous report indicated that human MIP-la but not MIP-ip, could induce a small but detectable level of calcium flux in human neutrophils (30). When recombinant human MIP-la was injected into human skin to examine the in vivo role of this chemokine, rapid infiltration of neutrophils was observed prior to the appearance of other cell types, such as monocytes and lymphocytes (31). 

Cell Cycle Analysis and Kinetics Apoptosis Calcium Flux Chromosome Analysis Micronuclei Analysis Intracellular pH Intracellular Glutathione Oxidative Burst Cell Viability... 

A considerable number of transcription factors have reactive cysteine residues, which enable them to respond to the redox conditions in the cell. Since cadmium perturbs redox homeostasis, it can affect this class of transcription factors. If cadmium can displace the tetra-coordinate zinc atoms in zinc finger-containing transcription factors, it will affect them as well. Many of the pathways involving activation and inactivation of transcription factors involve kinases and phosphatases, themselves under the intricate control of calcium fluxes. It is therefore no surprise that cadmium will exert effects on the activity of transcription factors, the activation of proto-oncogenes, and thereby on gene expression (Figure 20.8i and i ). 

Cohen AJ, Bunn PA, Franklin W, Magill-Solc C, Hartmann C, Helfrich B, Gilman L, Folkvord J, Helm K, Miller YE (1996) Neutral endopeptidase Variable expression in human lung, inactivation in lung cancer, and modulation of peptide-induced calcium flux. Cancer Res 56(4) 831-839. 

To relate the isotopic composition of marine calcium to variations in the calcium cycle requires characterization of the 5 Ca values of the sources and sinks of Ca to the oceans, and estimates of the Ca fluxes. Neither is well documented presently. Estimates of the calcium fluxes from Milliman (1993) are shown in Table 3. There are six analyses of 5 Ca from mid-ocean ridge hydrothermal vents, and these average -1-0.2 + 0.2 (Zhu and MacDougall... 

The S-HT variants such as H452Y have been associated with decreased calcium flux in response to clozapine that likely results from decreased Gq signaling (97,102-106). It is interesting to note that while depression has not been consistently associated with S-HT polymorphisms, such as -1348A/G in the promoter, no response to the antidepressant citralopram may be associated with in these... 

Calcium channel blockade interferes with prejunctional calcium flux at the neuromuscular junction, and verapamil (but probably not nifedipine) can thus potentiate neuromuscular blockade. Magnesium sulphate, used in management of pre-eclampsia, has a similar effect, and the two drugs in combination may themselves cause neuromuscular block. 

The bipyridines increase myocardial contractility by increasing inward calcium flux in the heart during the action potential they may also alter the intracellular movements of calcium by influencing the sarcoplasmic reticulum. They also have an important vasodilating effect. Inhibition of phosphodiesterase results in an increase in cAMP and the increase in contractility and vasodilation. 

The mechanism of action of the vitamin D metabolites remains under active investigation. However, calcitriol is well established as the most potent agent with respect to stimulation of intestinal calcium and phosphate transport and bone resorption. Calcitriol appears to act on the intestine both by induction of new protein synthesis (eg, calcium-binding protein and TRPV6, an intestinal calcium channel) and by modulation of calcium flux across the brush border and basolateral membranes by a means that does not require new protein synthesis. The molecular action of calcitriol on bone has received less attention. However, like PTH, calcitriol can induce RANK ligand in osteoblasts and proteins such as osteocalcin, which may regulate the mineralization process. The metabolites 25(OH)D and 24,25(OH)2D are far less... 

The use of new transcriptome information for discovery of novel drug candidates is desirable, as the control of schistosomiasis relies mostly on the use of a single drug, praziquantel, a heterocyclic pyrazino-isoquinolone. This drug exerts multiple effects, such as damage to the tegumental membrane, changes in calcium flux and muscular contractions in the parasite by a mechanism or mechanisms that are not... 

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