2019 Volume 29 Issue 2-3 Pages 119-131
The aim of the present study is to investigate the protective effect of chelators against the decline of ependymal ciliary beat frequency (CBF) in mice induced by methyl mercury (MeHg). CBF decreased after mice were given MeHg (20 mg/L) in drinking water for eight days. When dimercaptosuccinic acid (DMSA) was injected subcutaneously once a day from Day 6 to Day 8, CBF recovered from the decrease that was found in MeHg-drinking mice, but the other mercury chelators had no effect. The mercury contents in blood, the cerebrospinal fluid and the frontal lobe decreased after the DMSA treatment in comparison with the group that was only given MeHg, but the decrease did not depend on the dose of DMSA. In addition, CBF decreased during Day 3 to Day 5 after the single intraperitoneal injection of MeHg. However, the CBF did not recover in spite of a single injection of DMSA three days after the MeHg injection. Next, a brain slice prepared from healthy mice was set on a glass-bottom dish and artificial cerebrospinal fluid (CSF) was circulated. When MeHg was added to the CSF, CBF decreased. However, the addition of DMSA in the dish did not suppress the decrease of the CBF induced by MeHg treatment. In conclusion, these results may suggest that MeHg does not affect genes involved in the ciliary movement but influences the substances related to the movement.
