Methylmercury intoxication activates nitric oxide synthase in chick retinal cell culture
Braz. j. med. biol. res
; 39(3): 415-418, Mar. 2006. tab
Article
en En
| LILACS
| ID: lil-421370
Biblioteca responsable:
BR1.1
RESUMO
The visual system is a potential target for methylmercury (MeHg) intoxication. Nevertheless, there are few studies about the cellular mechanisms of toxicity induced by MeHg in retinal cells. Various reports have indicated a critical role for nitric oxide synthase (NOS) activation in modulating MeHg neurotoxicity in cerebellar and cortical regions. The aim of the present study is to describe the effects of MeHg on cell viability and NOS activation in chick retinal cell cultures. For this purpose, primary cultures were prepared from 7-day-old chick embryos retinas were aseptically dissected and dissociated and cells were grown at 37°C for 7-8 days. Cultures were exposed to MeHg (10 µM, 100 µM, and 1 mM) for 2, 4, and 6 h. Cell viability was measured by MTT method and NOS activity by monitoring the conversion of L-[H³]-arginine to L-[H³]-citrulline. The incubation of cultured retina cells with 10 and 100 µM MeHg promoted an increase of NOS activity compared to control (P < 0.05). Maximum values (P < 0.05) were reached after 4 h of MeHg incubation increases of 81.6 ± 5.3 and 91.3 ± 3.7 percent, respectively (data are reported as mean ± SEM for 4 replicates). MeHg also promoted a concentration- and time-dependent decrease in cell viability, with the highest toxicity (a reduction of about 80 percent in cell viability) being observed at the concentration of 1 mM and after 4-6 h of incubation. The present study demonstrates for the first time the modulation of MeHg neurotoxicity in retinal cells by the nitrergic system.
Texto completo:
1
Colección:
01-internacional
Base de datos:
LILACS
Asunto principal:
Retina
/
Óxido Nítrico Sintasa
/
Compuestos de Metilmercurio
Límite:
Animals
Idioma:
En
Revista:
Braz. j. med. biol. res
Asunto de la revista:
BIOLOGIA
/
MEDICINA
Año:
2006
Tipo del documento:
Article
/
Congress and conference
País de afiliación:
Brasil
Pais de publicación:
Brasil