Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030193 (pain)
 261,466 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Because of computed tomography (CT) and digital subtraction angiography (DSA), other diagnostic procedures assisted by urovascular contrast media (CM) have decreased, but the annual total remains at 10 to 11 million procedures since 1980. This trend, expected to continue, suggests that CM will remain vital to medical imaging. The current nonionic CM are not universally affordable, and may elicit pain in peripheral angiography. The author and co-workers explored conversion of ionic into nonionic CM, and have arrived at Ioxilan, 5-(N-2,3-dihydroxypropylacetamido)-2,4,6-triiodo-N-(2-hydroxyethyl )-N'-(2,3- dihydroxypropyl)-isophthalamide; a stable, water-soluble and well-tolerated CM. Ioxilan has unexpectedly low osmolality (570 mOsm at 300 mgI/mL), attributable to the region of double-methylenes that, by hydrophobic bonding, transiently associates the Ioxilan molecules. The high overall hydrophilicity, and thus good biological tolerance, of Ioxilan is accomplished by masking the hydrophobic region with a hydrophilic group. The author suggests that improved urovascular nonionic CM can be designed using this principle.
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PMID:The need for improved contrast media. Ioxilan: updating design theory. 305 36

Vascular pain caused by contrast media (CM) cannot be quantified by subjective patient reports or manifest pain reactions in experimental animals. Therefore, conditioned taste aversion (CTA), a psychopharmacological method, was used in double-blind femoral arteriography in rats to compare a new nonionic monomeric CM, ioxilan, with iohexol, iopamidol (all at 350 mgI/mL) and 22% sorbitol. A chronically implanted femoral artery catheter was used to inject 0.2 mL/kg body weight. By measuring the intake of water laced with the flavor that thirsty rats had learned to associate with the injection, the degree of aversion, assumed proportional to pain, was determined. Ioxilan (690 mOsm) produced the least pain, followed by iopamidol (810 mOsm), iohexol (844 mOsm) and sorbitol (1410 mOsm). Since all test substances are highly and similarly hydrophilic and nonionic, the intensity of vascular pain must depend on solution osmolality, rather than on chemotoxicity or ionicity. Compounds of the lowest osmolality, ig, ioxilan, elicit the least vascular pain.
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PMID:Current contrast media and ioxilan. Comparative evaluation of vascular pain by aversion conditioning. 319 69