Pathology of the heart after overhydration with glycine solution in the mouse

Glycine solution, which is widely used for irrigation in endoscopic surgery, has recently been suspected to have acute or subacute cardiotoxic properties. Therefore, the hearts of 46 mice that survived an intravenous infusion of 0.21/kg glycine 1.1%, 1.5% or 2.2% were examined for pathological alterations between 2 h and 7 weeks after the infusions. Half the animals developed extensive dilatation of the interstitium. Hypoxic events were evidenced by leakage of myoglobin from myocytes in 32 animals and correlated with dilatation of the interstitium. Focal necrosis with an inflammatory cell reaction and replacement of the myocardial tissue with granulation and fibrous tissue were observed after five glycine infusions. Pathological changes were mild or absent in five mice given mannitol solution and in three to which no infusion was given.