Modulation of ion transport

Oxidant Stress and the Heart Modulation of Ion Transport Mechanisms During Ischaemia and... 

If cellular redox state, determined by the glutathione status of the heart, plays a role in the modulation of ion transporter activity in cardiac tissue, it is important to identify possible mechanisms by which these effects are mediated. Protein S-,thiolation is a process that was originally used to describe the formation of adducts of proteins with low molecular thiols such as glutathione (Miller etal., 1990). In view of the significant alterations of cardiac glutathione status (GSH and GSSG) and ion-transporter activity during oxidant stress, the process of S-thiolation may be responsible for modifications of protein structure and function. 

B. Novel Means Based on Modulation of Ion Transport Processes... 

Kmnersley, A.M. and Lin, F. (2000) Receptor modifiers indicate that 4-aminobutyric acid (GABA) is a potential modulator of ion transport in plants. /. Plant Growth ReguL, 32,65-76. 

MacNaughton WK, Van Sickle MD, Keenan CM, Cushing K, Mackie K, Sharkey KA (2004) Distribution and function of the cannabinoid-1 receptor in the modulation of ion transport in the guinea pig ileum relationship to capsaicin-sensitive nerves. Am J Physiol Gastrointest Liver Physiol 286 G863-G871... 

A noise that has a clearly distinct origin from noise discussed in previous sections is the electric noise that originates in modulation of ion transport by fluctuations in system conductance. These temporal fluctuations can be measured, at least in principle, even in systems at equilibrium. Such a measurement was conducted by Voss and Clark in continuous metal films (44). The idea of the Voss and Clark experiment was to measure low-frequency fluctuations of the mean-square Johnson noise of the object. In accordance with the Nyquist formula, fluctuations in the system conductance result in fluctuations in the spectral density of its equilibrium noise. Measurement of these fluctuations (that is, measurement of the noise of noise) yields information on conductance fluctuations of the system without the application of any external perturbations. The samples used in these experiments require rather large amplitude conductance fluctuations to be distinguished from Johnson noise fluctuations because of the intrinsic limitation of statistics. Voss and... 

Ion transport processes of the cornea and the conjunctiva can play an important role in maintaining intra- and extracellular fluid homeostasis, signal transduction, and intercellular communication. As all these functions may contribute to the modulation of drug transport (see Section IV.B), it is essential that the baseline ion transport processes in the cornea and the conjunctiva be understood. 

The final chapter, The Role of the Membrane Actions of Phenothiazines and Flavonoids as Functional Modulators by K. Michalak, O. Wesolowska, N. Motohashi and A. B. Hendrich, presents a very comprehensive review on important biological effects of phenothiazines and flavonoids due to interactions with membrane proteins and the lipid phase of membranes. The discussion includes the influence of these heterocycles on model and natural membranes, modulation of MDR transporters by these heterocycles, and the effects of these hetero cycles on ion channel properties. This review may attract much interest from medicinal and pharmaceutical chemists as well as heterocyclic chemists in the life science fields. 

Suga T, Takeuchi S, Nishide H (2011) Morphology-driven modulation of charge transport in radical/ion-containing, self-assembled block copolymer platform. Adv Mater 23(46) 5545-5549... 

Apart from very few exceptions, the entries in the main text do not contain drug names in their titles. Instead, drugs that are commonly used all over the world are listed in the Appendix. Also included in the Appendix are four-extensive sections that contain tables listing proteins such as receptors, transporters or ion channels, which are of particular interest as drug targets or modulators of drug action. 

Armstrong FA, Cox PA, Hill HAO, Lowe VJ, Ohver BN. 1987. Metal-ions and complexes as modulators of protein interfacial electron-transport at graphite-electrodes. J Electroanal Chem217 331-366. 

There is growing evidence implicating Na+-dependent solute transporters and intracellular as well as extracellular Ca2+ in the physiological regulation of the paracellular pathway [81,203,204], Such modulation of paracellular permeability is especially important for drugs such as peptides and oligonucleotides that exhibit poor permeability characteristics across both the cornea and the conjunctiva [150,152,154,155], In addition, ion transporters such as Cl and Ca2+ channels have been implicated in macromolecular transport (see Sections IV.B.2 and IV.B.4). In the following discussion, some key ion transport processes and their possible roles in solute transport across epithelial tissues are summarized. 

CE Crosson, RW Beuerman, SD Klyce. (1984). Dopamine modulation of active ion transport in rabbit corneal epithelium. Invest Ophthalmol Vis Sci 25 1240-1245. 

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