| Description |
The effects of mercuric chloride on both mixed and highly purified cultures of neurons and non-neuronal (glial) cells were studies. Cultures were prepared from the sympathetic ganglia of 11 day chick embryos and treated with mercuric chloride (0.0001-100 um-M) for two or three days. Protein content, acetyl cholinesterase activity, 3H-thymidine incorporation, and 14C-leucine incorporation were measured, and the following results were obtained. First, the effects of mercuric chloride varied in a complex manner with both concentration and time of exposure. For example, mixed cultures treated for two day showed (a) increased total protein content and 14C-leucine incorporation at low concentrations, (b) decreased total protein content and 14C-leucine incorporation at high concentrations, (c) increased acetyl cholinesterase activity at most concentrations, and (d) decreased 3-H-thymidine incorporation at the highest concentration. In cultures treated for three days, essentially all concentrations of mercuric chloride either inhibited or had no effect on any of these biochemical quantities. Second, neurons were sensitive to concentrations of mercuric chloride as low as 0.0001-0.001 um-M while the non-neuronal cells were generally unaffected by concentrations less than 1 um-M. Third, most of the effects of mercuric chloride resulted from direct actions on either the neurons or non-neuronal cells. For example, various concentrations of mercuric chloride had identical effects on the activity of the neuronal enzyme acetyl cholinesterase in the presence and absence of non-neuronal cells (i.e., in mixed and highly purified neuronal cultures, respectively). |
