Ebselen protects glutamate uptake inhibition caused by methyl mercury but does not by Hg2+.
Alterations of the neurotransmitter release systems in CNS have been reported in a variety of neuropathological processes associated with heavy metal toxicity. Neurotoxic effects of mercurials were investigated in vitro in cerebral cortex slices from young rats. The present study indicates that: (i) the environmental contaminants methylmercury (MeHg) and mercuric chloride (Hg2+) (50 microM) inhibited the glutamate net uptake from the cerebral cortex of 17-day-old rats; (ii) ebselen (10 microM) reverted the MeHg-induced inhibition of glutamate net uptake but did not protect the inhibition caused by Hg2+. At same time, we investigated another diorganochalcogenide, diphenyl diselenide (PhSe)2 and it was observed that this compound did not revert the action of MeHg or Hg2+; (iii) in addition, we observed that exposure of slices to 50 microM MeHg and Hg2+ for 30 min followed by Trypan blue exclusion assay resulted in 58.5 and 67.5% of staining cells, respectively, indicating a decrease in cell viability. Ebselen protected slices from the deleterious effects of MeHg, but not of Hg2+ on cell viability. Conversely, ebselen did not modify the reduction of MTT caused by MeHg and Hg2+; (iv) the protective effect of ebselen on MeHg-induced inhibition of glutamate net uptake seems to be related to its ability in maintaining cell viability.
Moretto
M B
MB
Departamento de Análises Clínicas e Toxicológicas, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, RS, Brazil.
Funchal
C
C
Santos
A Q
AQ
Gottfried
C
C
Boff
B
B
Zeni
G
G
Pureur
R Pessoa-
RP
Souza
D O
DO
Wofchuk
S
S
Rocha
J B T
JB
D000818:Animals; D001393:Azoles / Q000494:pharmacology*; D001555:Benzene Derivatives / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D002540:Cerebral Cortex / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D018698:Glutamic Acid / Q000378:metabolism*; D066298:In Vitro Techniques; D054833:Isoindoles; D008627:Mercuric Chloride / Q000633:toxicity*; D008767:Methylmercury Compounds / Q000633:toxicity*; D018696:Neuroprotective Agents / Q000494:pharmacology*; D016566:Organoselenium Compounds / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D001393:Azoles; D001555:Benzene Derivatives; D054833:Isoindoles; D008767:Methylmercury Compounds; D018696:Neuroprotective Agents; D016566:Organoselenium Compounds; C061132:diphenyldiselenide; D018698:Glutamic Acid; C042986:ebselen; D008627:Mercuric Chloride