B. H. Choi, L. Lapham
Feb 1, 1981
Experimental and molecular pathology
Abstract Monolayer cultures of human fetal astrocytes (HFA) were exposed to 0.01 m M methyl-mercuric chloride (MMC) for 30 to 60 min and were then treated with medium containing 1.0 m M meso-2,3-dimercaptosuccinic acid (DMSA), a newly synthesized complexing agent for heavy metals. Within 30 to 40 min of DMSA addition, the coagulated membrane of astrocytes injured by MMC recovered to a normal state with return of active filopodial and ruffling activity. Addition of DMSA prior to MMC exposure prevented the occurrence of degenerative changes in astrocytic membranes. Exposures to 1.0 m M DMSA alone for 24 hr did not cause degenerative changes in HFA. Thus DMSA appears to be an extremely effective agent in complexing methylmercury either in the membrane or in the culture medium with no demonstrable toxic actions on HFA in culture. The minute to minute sequential changes of HFA before and after exposures to MMC and DMSA were recorded with time-lapse cinematography and were repeated numerous times with similar results. Electron microscopic study revealed separation of membranes from cell bodies and processes associated with marked edema of the underlying matrix. The cytoskeletal elements associated with membranes became dissociated and disappeared after MMC exposure but promptly returned to normal with addition of DMSA and replacement with normal fresh culture medium.