Cell volume was determined by measuring [14C]-3-O-methyl glucose uptake in astroglial-enriched primary cultures. Control cell volume was 3.20μl/mg protein. After incubation in 10 5M HgCl2 for 60 minutes, there was a 71% increase in cell volume. This increase was partially inhibited in the presence of the α1 receptor agonist, phenylephrine, or by the α2 receptor agonist clonidine, and was completely reversible by their respective antagonists, prazosine and yohimbine. The β receptor agonist, isoproterenol, which in itself increased cell volume, and 5-hydroxytryptamine (5HT) did not affect the HgCl2-induced changes in cell volume. 10 5M CH3HgCl increased cell volume by 26% after 30 minutes of incubation. This increase was not significantly influenced by adrenoceptor agonists or 5HT.
It therefore seems that mercurial-induced changes in cell volume can be regulated by astroglial receptor stimulation.
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