title: CSF cation changes following subarachnoid injection of iohexol and metrizamide in rabbits.
abstract: Forty anaesthetized rabbits were injected subarachnoidally with equimolal doses, 0.48 mmol/kg body weight (= 185 mg I/kg), of iohexol and metrizamide, administered in solutions iso- and hyperosmolal to the CSF. Concentrations of Na, K, Ca and Mg in the CSF were determined before and 3 hours after the contrast medium injections. Iso-osmolal iohexol caused a uniform decrease in all four cations, which was believed to be a simple dilution. The hyperosmolal solution of iohexol caused a significant relative increase in Ca compared with Na, K and Mg. Both metrizamide solutions caused an increase in Ca over its pre-injection level and a significant relative increase of both Ca and Mg as compared with Na and K. The changes caused by the three latter solutions were consistent with an increase in the blood-brain barrier permeability.
mesh_terms: D000818:Animals; D001812:Blood-Brain Barrier / Q000187:drug effects; D001834:Body Water / Q000378:metabolism; D003287:Contrast Media / Q000378:metabolism / Q000494:pharmacology*; D004573:Electrolytes / Q000097:blood / Q000134:cerebrospinal fluid*; D007278:Injections, Spinal; D007463:Iodobenzoates / Q000494:pharmacology*; D007472:Iohexol; D008793:Metrizamide / Q000378:metabolism / Q000494:pharmacology*; D009994:Osmolar Concentration; D011817:Rabbits; D013346:Subarachnoid Space / Q000378:metabolism; D014283:Triiodobenzoic Acids / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D003287:Contrast Media; D004573:Electrolytes; D007463:Iodobenzoates; D014283:Triiodobenzoic Acids; D007472:Iohexol; D008793:Metrizamide