Effects of mercury intoxication on the response of horizontal cells of the retina of thraira fish (Hoplias malabaricus)
Contribuinte(s) |
Universidade Estadual Paulista (UNESP) |
---|---|
Data(s) |
20/05/2014
20/05/2014
01/07/2006
|
Resumo |
Methyl mercury (MeHg) is highly neurotoxic, affecting visual function in addition to other central nervous system functions. The effect of mercury intoxication on the amplitude of horizontal cell responses to light was studied in the retina of the fish Hoplias malabaricus. Intracellular responses were recorded from horizontal cells of fish previously intoxicated with MeHg by intraperitoneal injection (IP group) or by trophic exposure (T group). Only one retina per fish was used. The doses of MeHg chloride administered to the IP group were 0.01, 0.05, 0.1, 1.0, 2.0, and 6.0 mg/kg. The amplitudes of the horizontal cell responses were lower than control in individuals exposed to 0.01 (N = 4 retinas), 0.05 (N = 2 retinas) and 0.1 mg/kg (N = 1 retina), whereas no responses were recorded in the 1.0, 2.0, and 6.0 mg/kg groups. T group individuals were fed young specimens of Astyanax sp previously injected with MeHg corresponding to 0.75 (N = 1 retina), 0.075 (N = 8 retinas) or 0.0075 (N = 4 retinas) mg/kg fish body weight. After 14 doses, one every 5 days, the amplitude of the horizontal cell response was higher than control in individuals exposed to 0.075 and 0.0075 mg/kg, and lower in individuals exposed to 0.75 mg/kg. We conclude that intoxication with MeHg affects the electrophysiological response of the horizontal cells in the retina, either reducing or increasing its amplitude compared to control, and that these effects are related to the dose and/or to the mode of administration. |
Formato |
987-995 |
Identificador |
http://dx.doi.org/10.1590/S0100-879X2006000700017 Brazilian Journal of Medical and Biological Research. São Paulo: Associação Bras Divulg Cientifica, v. 39, n. 7, p. 987-995, 2006. 0100-879X http://hdl.handle.net/11449/8621 10.1590/S0100-879X2006000700017 S0100-879X2006000700017 WOS:000239624200017 2-s2.0-33746345629 WOS000239624200017.pdf |
Idioma(s) |
eng |
Publicador |
Associação Brasileira de Divulgação Científica (ABRADIC) |
Relação |
Brazilian Journal of Medical and Biological Research |
Direitos |
openAccess |
Palavras-Chave | #methyl mercury #horizontal cells #electrophysiology #Hoplias malabaricus #retina |
Tipo |
info:eu-repo/semantics/article |