Losses of immunoreactive parvalbumin amacrine and immunoreactive alphaprotein kinase C bipolar cells caused by methylmercury chloride intoxication in the retina of the tropical fish Hoplias malabaricus

Bonci, Daniela Maria Oliveira; Lima, Sônia Maria Rolim Rosa; Grötzner, Sônia Regina; Ribeiro, Ciro Alberto de Oliveira; Hamassaki‐Britto, Dânia Emi; Ventura, Dora Fix

doi:10.1590/s0100-879x2006000300011

Cited by 24 publications

(17 citation statements)

References 32 publications

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“…The following primary antibodies were used: anti-calretinin (1:500, Chemicon AB 1550, Temecula, CA, USA) (10,11), antiChAT (1:100, Chemicon AB144P) (11), anticalbindin (1:200, Sigma C8666) (1) and anti-PKC-α (1:1000, Sigma P4334) (12,13). Retinal sections were incubated with the primary antibodies overnight and with Alexa-488 or TRITC-conjugated secondary antibodies (1:1000 or 1:200, respectively; Molecular Probes) for 2 h. Propidium iodide labeling was performed after the secondary antibody washes.…”

Section: Immunohistochemistrymentioning

confidence: 99%

Immunohistochemical characterization of the chick marginal retina

Lima

Saito

Hamassaki‐Britto

et al. 2007

Braz J Med Biol Res

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The retina is a highly differentiated tissue with a complex layered structure that has been extensively characterized. However, most of the previous studies focused on the histology of the central retina while little is known about the cellular composition, organization and function of the marginal retina. Recent research has identified a subpopulation of multipotential progenitor cells in the marginal regions of the retina, closest to the ciliary body ("ciliary marginal zone"). These cells are capable of differentiation in response to an appropriate stimulus. Thus, it is possible that the structure and composition of the marginal retina are distinct from those of the central retina to accommodate the potential addition of newly formed neurons. To characterize the cellular profile of the chick marginal retina, we labeled it immunohistochemically for markers whose staining pattern is well established in the central retina: calbindin, calretinin, protein kinase C, and choline acetyltransferase. Calbindin was present at very low levels in the marginal retina putative photoreceptor layer. Calretinin-positive horizontal cells were also sparse close to the ciliary marginal zone. The bipolar cells in the marginal outer plexiform layer were positive for anti-protein kinase C antibodies, but the density of labeling was also decreased in relation to the central retina. In contrast, the marginal starburst cholinergic amacrine cell pattern was very similar to the central retina. From these data we conclude that the structure of the marginal retina is significantly different from that of the central retina. In particular, the expression of late retina markers in the marginal retina decreased in comparison to the central retina.

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Section: Immunohistochemistrymentioning

confidence: 99%

Immunohistochemical characterization of the chick marginal retina

Lima

Saito

Hamassaki‐Britto

et al. 2007

Braz J Med Biol Res

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“…Morphological analysis did not suggest a complete absence of activity in the exposed cells, as found in the electrophysiological experiments. In fish injected with the two highest ip doses (2 and 6 mg MeHg/kg) a dose-dependent reduction of the number of cells with immunoreactivity to parvalbumin was detected, probably amacrine and displaced amacrine cells (31,32) and bipolar cells of the ON type, with immunoreactivity to protein kinase C. The quantification of these data should provide a better understanding of the electrophysiological data.…”

Section: Discussionmentioning

confidence: 93%

“…At the same time as the present study, a morphological study was carried out on the effects of MeHg intoxication on the retina (31,32). For each retina used in an electrophysiological experiment the other retina from the same fish was used for the morphological study.…”

Section: Discussionmentioning

confidence: 99%

Effects of mercury intoxication on the response of horizontal cells of the retina of thraira fish (Hoplias malabaricus)

Tanan

Ventura

Souza

et al. 2006

Braz J Med Biol Res

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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.

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“…Mercury causes depletion of the principal cellular antioxidants, with high affinity for the thionic group (Azevedo, 2003), the functional group of the amino acid, cysteine. Beyond effects on the retinal cell (eg, Bonci et al, 2006), various other cells of the nervous system appear to be affected by exposure to the metal (Nascimento & Chasin, 2001). The observation that methylmercury induces oxidative stress in the brain of house mice (Yee & Choi, 1994) led Aschner et al (1995Aschner et al ( , 1998Aschner et al ( , 2000 to consider that there are two critical components in the neurotoxicology of methylmercury: the increase in extracellular concentration of glutamate as a result of alterations in the astrocyte function (Aschner, Vitarella, Allen, Conklin, & Cowan, 1998), as well as direct interaction with the cysteine transporter, causing a decrease in the concentration of cysteine for synthesis of glutathione; and interference with the function of the astrocyte transporter of glutamate, causing an increase in the extracellular concentration of this neurotransmitter (Morken, Sonnewald, Aschner, & Syversen, 2005); this activity is modulated by adenosine (Aschner, Mullaney, Wagoner, Jr., Lash, & Kimelberg, 1995) and by glutathione (Kaur, Aschner, & Syversen, 2006).…”

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confidence: 99%

Effects of Trophic Poisoning with Methylmercury on the Appetitive Elements of the Agonistic Sequence in Fighting-Fish (Betta Splendens)

et al. 2007

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The aggressive display in Betta splendens is particularly prominent, and vital to its adaptation to the environment. Methylmercury is an organic variation of Hg that presents particularly pronounced neuro-behavioral effects. The present experiments aim to test the effect of acute and chronic poisoning with methylmercury on the display in Bettas. The animals were poisoned by trophic means in both experiments (16 ug/kg in acute poisoning; 16 ug/kg/day for chronic poisoning), and tested in agonistic pairs. The total frequency of the display was recorded, analyzing the topography of the agonistic response. The methylmercury seems to present a dose-and detoxification-dependent effect on these responses, with a more pronounced effect on motivity in acute poisoning and on emotionality in the chronic poisoning. It is possible that this effect could be mediated by alteration in the mono-amino-oxidase systems. Keywords: methylmercury, aggression, emotional behavior, Betta splendensEl despliegue agresivo en la Betta splendens es especialmente prominente y es vital para su adaptación al medio ambiente. Metil-mercurio es una variación orgánica de Hg que presenta efectos neuro-conductuales especialmente pronunciados. Los experimentos actuales intentan poner aprueba el efecto de envenenamiento agudo y crónico con metil-mercurio sobre el despliegue en Bettas. Los animales fueron envenenados tróficamente en ambos experimentos (16 ug/kg e el envenenamiento agudo) y probados en parejas agonistas. Se registró la frecuencia total del despliegue, analizando la topografía de la respuesta agonista. El metil-mercurio parece presentar un efecto dependiente de la dosis y de la detoxificación sobre estas respuestas, con un efecto más pronunciado sobre la motilidad en el envenenamiento agudo y sobre la emotividad en el envenenamiento crónico. Posiblemente, este efecto podría mediarse por la alteración en los sistemas de mono-amino-oxidasa.

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Losses of immunoreactive parvalbumin amacrine and immunoreactive alphaprotein kinase C bipolar cells caused by methylmercury chloride intoxication in the retina of the tropical fish Hoplias malabaricus

Cited by 24 publications

References 32 publications

Immunohistochemical characterization of the chick marginal retina

Immunohistochemical characterization of the chick marginal retina

Effects of mercury intoxication on the response of horizontal cells of the retina of thraira fish (Hoplias malabaricus)

Effects of Trophic Poisoning with Methylmercury on the Appetitive Elements of the Agonistic Sequence in Fighting-Fish (Betta Splendens)

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