title: Further support for the glucose hypothesis of metrizamide toxicity. The effect of metrizamide and glucose analogue-free contrast media on hexokinase.
abstract: Metrizamide neurotoxicity has been hypothesized to be caused by an inhibitory effect of the drug on glucose metabolism. Metrizamide contains a glucose side chain, and glucose analogues including metrizamide have been shown to be inhibitors of hexokinase, an enzyme that is central to cerebral glucose metabolism. We studied the effect of the nonionic contrast agents iohexol, iotrol, and iopamidol, and the ionic contrast meglumine diatrizoate, on hexokinase in vitro. Although metrizamide reproducibly caused competitive inhibition of the reaction, the nonglucose contrast agents had no significant effect on the enzyme. These results add further support for the glucose hypothesis of metrizamide neurotoxicity.
mesh_terms: D003287:Contrast Media; D003974:Diatrizoate Meglumine; D005947:Glucose; D006593:Hexokinase; D007472:Iohexol; D007479:Iopamidol; D008793:Metrizamide / Q000633:toxicity*; D009422:Nervous System Diseases / Q000139:chemically induced; D014283:Triiodobenzoic Acids
chemical_list: D003287:Contrast Media; D014283:Triiodobenzoic Acids; C033300:iotrolan; D003974:Diatrizoate Meglumine; D007472:Iohexol; D006593:Hexokinase; D005947:Glucose; D007479:Iopamidol; D008793:Metrizamide