Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: KEGG:D01817 (Iohexol)
 504 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The influence on contractile force (CF) and the propensity for ventricular fibrillation (VF) from infusing the non-ionic contrast medium iohexol during normal (75 cm H2O) and reduced perfusion pressure (35 cm H2O) were investigated in the isolated rabbit heart. Both during normal and reduced perfusion pressure iohexol (150 mg I/ml) with oxygen saturation caused a smaller reduction of CF than iohexol without oxygen. During reduced pressure iohexol with sodium addition (28 mM NaCl) caused less depression of CF than iohexol without sodium. The combination of sodium addition and oxygen saturation had the least influence on CF. Iohexol (350 mg I/ml) without sodium had a similar fibrillatory propensity during both normal and reduced pressure. Enriching iohexol with 28 mM NaCl decreased the risk of VF. The decrease was similar during both normal and reduced pressure. The risk of VF from oxygen saturation of iohexol (350 mg I/ml, without sodium) was similar during both normal and reduced pressure. It is concluded that a small addition of sodium and/or oxygen saturation of a non-ionic monomeric contrast medium have beneficial effects on the heart both during normal perfusion pressure and during ischemia.
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PMID:Sodium addition and/or oxygen saturation of iohexol during normal and reduced perfusion pressure. Effects on contractile force and risk of ventricular fibrillation in the isolated rabbit heart. 226 4

Water-soluble nonionic x-ray contrast media have greatly improved the quality and safety of myelography. Toxic side effects are still observed however. The side effects are generally worse with the first nonionic agent, metrizamide, which has a glucoselike side group. Two in vitro models were developed to examine the effects of contrast media on glucose metabolism. Using rat hippocampus slices, the authors observed significant depression of carbon dioxide production by metrizamide and by deoxyglucose, a known metabolic inhibitor. Iohexol and iopamidol did not cause significant depressions. In rat brain synaptosomes the authors did not observe a depression of the uptake of deoxyglucose 14C by any media tested. These studies indicate that metrizamide can create metabolic depression but that it does not compete with glucose for the membrane glucose carrier.
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PMID:In vitro models for testing the metabolic effects of myelographic contrast media. 319 46

The comparative immediate effects of ionic and nonionic contrast agents on coronary blood flow and regional function have not been studied. Therefore, subselective intracoronary injections of iohexol and sodium meglumine diatrizoate (Renografin 76) were compared at different rates (1, 3, and 4 mL/sec) and volumes (2 and 4 mL). Open chest dogs were instrumented with electromagnetic flow probes, subendocardial ultrasonic crystals, and a subselective intracoronary catheter. The 2- and 4-mL volumes of Renografin infused at 3 mL/sec, caused reductions in coronary blood flow that were maximal at 2 to 3 seconds after injection. These changes were significant for the 4-mL dose (61 +/- 19 at control vs. 23 +/- 12 mL/min, mean +/- SD, P less than .01) but not for the 2-mL dose. Iohexol produced identical flow responses but regional function was not significantly altered, whereas Renografin caused significant depression at both dose levels. Injections of 4 mL of Renografin at 1 and 4 mL/sec caused maximal flow decrements at 4.5 and 2 seconds after injection, respectively. Again, iohexol caused identical responses. At these doses, the effects of iohexol on regional function were also identical to those of Renografin. Thus, despite differences in physical properties, no significant differences in early blood flow changes were detected between these two agents.
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PMID:Immediate effects of graded ionic and nonionic contrast injections on coronary blood flow and myocardial function. Implications for digital coronary angiography. 331 9

The inotropic effects of ionic (amidotriazoate) and nonionic (iohexol) contrast material were compared in isolated rat heart preparations. Left atria exposed to amidotriazoate for 10 mins exhibited a dose dependent depression of contractile force approximately twice as large as that brought about by equiosmolar sucrose. When the driving rate was reduced from 60 to 20 beats/min, this specific effect was abolished. The spontaneously beating hearts perfused with amidotriazoate-containing medium had increased resting tension and depressed force of contractions. These effects tended to spontaneously normalize. Upon bolus administration of amidotriazoate the contractile force of perfused hearts was briefly depressed and heart rate, action potential duration and time to peak force decreased. Iohexol did not produce any significant changes in the contractile force. The experiments illustrated direct action of ionic contrast dye on cardiac inotropy probably resulting from an immediate, slowly compensated ionic imbalance, and demonstrated a definite superiority of the nonionic contrast material.
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PMID:Inotropic effects of ionic and nonionic contrast materials in isolated heart preparations. 342 29

The chemistry of low-osmolality contrast agents is reviewed, the effects of these agents on vascular and organ physiology are compared with the effects of conventional ionic contrast media, and guidelines for intravascular use of the low-osmolality agents in selected high-risk patients are presented. Three low-osmolality contrast agents, the nonionic media iohexol (Omnipaque, Winthrop-Breon) and iopamidol (Isovue, Squibb) and the dimeric medium ioxaglate meglumine-sodium (Hexabrix, Mallinckrodt) have recently been introduced into the contrast-media market. Compared with conventional ionic contrast media, these new agents demonstrate approximately one third of the osmolality per given iodine concentration (degree of roentgenographic opacification). Therefore, the risks of hyperosmolarity-induced reactions to contrast media are lower with the new agents. The low-osmolality agents may be associated with a reduced incidence of contrast-media-induced hypersensitivity reactions. Because of their lower osmolality, these agents produce less vessel dilation, vascular endothelial damage, and associated pain and discomfort than equi-iodine concentrations of the conventional ionic media. They also demonstrate a reduction in the incidence and severity of contrast-media-induced renal vasoconstriction and proteinuria, hemodynamic alterations, negative chronotropic effects, depression of myocardial contractility, and neurotoxicity in the presence of an altered blood-brain barrier. These low-osmolality agents produce fewer undesirable physiological effects than conventional contrast agents, but the cost of the new products can be more than 10 times as great. Therefore, the new products should be used selectively in patients known to be at increased risk for reactions to intravascular contrast media. A scoring system was developed to permit rapid recognition of documented single or multiple risk factors and subsequent determination of whether to administer a low-osmolality agent.
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PMID:Evaluation of intravascular low-osmolality contrast agents. 378 Jan 59

In a prospective double blind randomised study in 25 consecutive patients a conventional ionic contrast medium (Urografin 370) was compared with the new non-ionic medium iohexol 350 ( Omnipaque ) in left ventriculography and coronary arteriography. In left ventriculography there was a clear patient preference for iohexol by both a visual analogue scale and independent observer assessment. Iohexol also induced a smaller increase in heart rate or decrease in systolic blood pressure than Urografin. In coronary arteriography iohexol resulted in a smaller reduction in heart rate and systolic blood pressure, a smaller maximum increase in RR interval, less prolongation of the PQ and QT intervals and QRS duration, and a lower incidence of induced chest pain, ST segment depression, or T wave deflection.
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PMID:Comparative trial of iohexol 350, a non-ionic contrast medium, with diatrizoate (Urografin 370) in left ventriculography and coronary arteriography. 637 3