Impaired in vitro accumulation of mercury in erythrocytes of acatalasemic mice

Abstract

In order to elucidate the role of erythrocyte catalase in the accumulation of mercury in erythrocytes, labeled erythrocytes and plasma were prepared by exposing normal and acatalasemic mice to radioactive mercury vapor (203Hg0: 6.8mg/m3) for 30 min. Labeled erythrocytes (or plasma) were mixed with unlabeled plasma (or erythrocytes) of normal or acatalasemic mice and incubated at 0 degrees C for 1 h. After incubation, the radioactivity of mercury in the erythrocytes and the plasma was measured by a gammascintillation counter. When labeled erythrocytes were incubated with unlabeled plasma, the ratio of mercury transferred from acatalasemic erythrocytes to normal plasma (11.6%) or to acatalasemic plasma (13.3%) were significantly higher than that from normal erythrocytes to normal plasma (1.8%) or to acatalasemic plasma (2.2%). When labeled normal (or acatalasemic) plasma was incubated with unlabeled normal or acatalasemic erythrocytes, the uptake of mercury by acatalasemic erythrocytes from normal plasma was 2.0%, and 1.2% from acatalasemic plasma, which tended to be lower than that by normal erythrocytes from normal plasma (3.4%) or from acatalasemic plasma (2.2%). The results indicated impaired accumulation of mercury in acatalasemic erythrocytes, suggesting the importance of catalase in taking up mercury in erythrocytes and protecting other organs from toxic effects of metallic mercury.