| pubmed-article:1037275 | pubmed:abstractText | The side effects of water soluble iodinated contrast media often mimic the clinical picture of acetylcholine intoxication. This prompted us to determine the amount of inhibition of human acetylcholinesterase by the following contrast media in vivo and in vitro: methyl glucamineiodipamide (Biligrafin forte), methylglucamine iothalamate (Conray 60), sodium-iothalamate (Conray 80). In vivo no correlation could be found between clinically manifest adverse reaction and enzyme inhibition after contrast media application. The in vitro values for 50% inhibition of erythrocyte acetylcholinesterase are: methylglucamine-iodipamide: 0.036 M, methylglucamine-iothalamate: 0.158 M, sodium-iothalamate: 0.3 M. Since in vitro, the maximal inhibitory effect of a given dose of contrast media can only be registered after a time interval when most of the contrast media in vivo has already been excreted by the kidneys or extracted by the liver, it seems very improbable that the enzyme inhibition seen in vitro should have any consequence whatsoever under clinical conditions. The in vitro inhibition of acetylcholinesterase is quickly reversible, with nearly all the activity regained 15 min after the removal of the contrast media. | lld:pubmed |
