Chelation drugs acting

The exposure, on the bacterial plasma membrane, of so many enzymes that, in the host, are well protected behind mitochondrial membranes, makes bacteria particularly susceptible to selectively toxic agents. The case of oxine, and other chelating drugs that act similarly, was discussed in Section 2.3. For the distribution of enzymes in mitochondria see Table 4.5. 

Catecholamines, 6 (1969) 200 Cell membrane transfer, 14(1977) 1 Central nervous system, drugs, transmitters and peptides, 23 (1986) 91 Centrally acting dopamine D2 receptor agonists, 29 (1992) 185 Chartreusin, 19 (1982) 249 Chelating agents, 20 (1983) 225... 

Comparison of their rate of onset and recovery of a treated mucosa has been made [37]. Fatty acids have strong and fast reactivity and allow for a fast recovery of the barrier function. Bile salts and salicylates are moderate, fast-acting agents with fast barrier-function recovery. Strong surfactants and chelators have strong or moderate reactivity and a slow recovery of barrier function. Solvents like dimethylsulfoxide and ethanol have moderate reactivity and act primarily as agents to improve drug miscibility in an aqueous environment. The enhancers listed above are also effective in the small intestine [22]. Enhancers that are more colon specific include ethylaceto-acetate, which must be first metabolically transformed to enamine [38]. 

Mechanism of Action A heavy metal antagonist that chelates copper, iron, mercury, lead to form complexes, promoting excretion of copper. Combines with cystine-forming complex, thus reducing concentration of cystine to below levels for formation of cystine stones. Exact mechanism for rheumatoid arthritis is unknown. May decrease cell-mediated immune response. May inhibit collagen formation. Therapeutic Effect Promotes excretion of copper, prevents renal calculi, dissolves existing stones, acts as anti-inflammatory drug. 

Molybdate is known to induce copper deficiency, ft was found that the administration of molybdenum compounds, particularly with added sulfate, impaired copper metabolism in ruminants. Tetrathiomolybdate has been used to treat patients who were intolerant to D-penicillanune, trientine, and zinc. Tetrathiomolybdate seems to act both by blocking the intestinal absorption of copper and keeping it in a metabolically inert chelated form, which is not taken up by the liver. However, it induces only a modest cupriuresis. There are also known toxic effects of tetrathiomolybdate on the skeletal system of growing animals. Thus one should be extremely careful in administering this compound. It should be considered as an experimental drug. 

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