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1.
Ecotoxicol Environ Saf ; 148: 693-701, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29172150

RESUMO

The increasing presence of pharmaceuticals in aquatic environments in the last decades, derived from human and veterinary use, has become an important environmental problem. Previous studies have shown that ibuprofen (IB) and carbamazepine (CBZ) modify physiological and biochemical processes in Senegalese sole (Solea senegalensis) in a temperature-dependent manner. In other vertebrates, there is evidence that both of these pharmaceuticals interfere with the 'arachidonic acid (AA) cascade', which is responsible for the biosynthesis of numerous enzymes that are involved in the osmoregulatory process. The present work aims to study the temperature-dependent effects of these two pharmaceuticals on several biochemical and molecular parameters in Senegalese sole. Regarding osmoregulation, Na+, K+ -ATPase enzyme activity was determined in the gills, kidney and intestine, and the expressions of both Na+, K+ -ATPase 1α-subunit isoforms (ATP1A1a and ATP1A1b) were quantified in gills. Gill prostaglandin-endoperoxide synthase-2 (PTGS2) gene expression and fatty acid composition were selected to determine the interference of both pharmaceuticals with the AA cascade. Senegalese sole juveniles, acclimatised at 15°C or 20°C, were exposed through intraperitoneal injection to IB (10mg/kg) and CBZ (1mg/kg) for 48h. Non-injected fish (Control) and those injected with the carrier (sunflower oil; S.O.), acclimated at each of the two temperatures, were used for comparison. The results show that IB directly affected the osmoregulatory mechanisms that alter gill and intestine Na+, K+ -ATPase activities. In addition, the copy number of ATP1A1a was higher at 20°C than at 15°C, which could be a direct response to the temperature variation. The gene expression of PTGS2 was affected by neither drug administration nor acclimation temperature. Nevertheless, detailed analysis of AA and eicosapentaenoic acid (EPA) percentages revealed a CBZ-derived effect in the fatty acid composition of the gills.


Assuntos
Aclimatação , Carbamazepina/toxicidade , Ácidos Graxos/metabolismo , Ibuprofeno/toxicidade , Transporte de Íons/efeitos dos fármacos , Temperatura , Poluentes Químicos da Água/toxicidade , Animais , Fenômenos Bioquímicos , Linguados/metabolismo , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Osmorregulação , Prostaglandina-Endoperóxido Sintases/metabolismo , Isoformas de Proteínas , ATPase Trocadora de Sódio-Potássio/metabolismo , Equilíbrio Hidroeletrolítico
2.
SAR QSAR Environ Res ; 28(9): 735-747, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29022372

RESUMO

The phenols are structurally heterogeneous pollutants and they present a variety of modes of toxic action (MOA), including polar narcotics, weak acid respiratory uncouplers, pro-electrophiles, and soft electrophiles. Because it is often difficult to determine correctly the mechanism of action of a compound, quantitative structure-activity relationship (QSAR) methods, which have proved their interest in toxicity prediction, can be used. In this work, several QSAR models for the prediction of MOA of 221 phenols to the ciliated protozoan Tetrahymena pyriformis, using Chemistry Development Kit descriptors, are reported. Four machine learning techniques (ML), k-nearest neighbours, support vector machine, classification trees, and artificial neural networks, have been used to develop several models with higher accuracies and predictive capabilities for distinguishing between four MOAs. They showed global accuracy values between 95.9% and 97.7% and area under Receiver Operator Curve values between 0.978 and 0.998; additionally, false alarm rate values were below 8.2% for training set. In order to validate our models, cross-validation (10-folds-out) and external test-set were performed with good behaviour in all cases. These models, obtained with ML techniques, were compared with others previously reported by other researchers, and the improvement was significant.


Assuntos
Antiprotozoários/farmacologia , Aprendizado de Máquina , Fenóis/farmacologia , Tetrahymena pyriformis/efeitos dos fármacos , Redes Neurais de Computação , Relação Quantitativa Estrutura-Atividade
3.
Environ Sci Pollut Res Int ; 23(20): 20937-20951, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27488709

RESUMO

The alerted presence in recent decades of pharmaceuticals has become an issue of environmental concern, and most of the mechanisms of biotransformation and biochemical and physiological responses to them in fish are still unknown, as well as the influence of water temperature in their ability to cope with them. This study aims to detect the main effects of two of the most widespread drugs on a set of physiological and biochemical markers in Solea senegalensis. Sole juveniles acclimatized at 15 and 20 °C were administered an intraperitoneal injection of the non-steroidal anti-inflammatory drug ibuprofen (IB; 10 mg/kg) and the anti-convulsant drug carbamazepine (CBZ; 1 mg/kg). Two days after the injection, liver, muscle and plasma were sampled. Liver enzymatic activities of 15 °C acclimated fish were more responsive to pharmaceuticals than those acclimated at 20 °C, especially for CYP450-related activities (7-ethoxyresorufin (EROD), 7-methoxyresorufin (MROD), 3-cyano-7-ethoxycoumarin (CECOD) and 7-benzyloxy-4-[trifluoromethyl]-coumarin-O-debenzyloxylase (BFCOD)) and uridine diphosphate glucuronosyltransferase (UDPGT). Cytosolic anti-oxidant enzyme activities and glutathione S-transferase (GST) did not show a clear effect of temperature. Glucose and transferase activities in plasma were not affected by the treatments, while ammonium, osmolality and lactate were affected by both pharmaceuticals. Plasma triglycerides were affected in a temperature-dependent manner, and creatinine was only responsive to CBZ injection. HSP70 levels in muscle were only affected by CBZ injection. Some of the physiological identified responses to IB and CBZ are proposed as endpoints in further chronic studies.


Assuntos
Poluentes Ambientais/farmacologia , Linguados/fisiologia , Temperatura , Animais , Fenômenos Bioquímicos , Biomarcadores/análise , Fígado/química , Fígado/efeitos dos fármacos
4.
Cienc. salud (Ciudad Autón. B. Aires) ; 6(1): 19-29, 2016. ilus, graf, tab
Artigo em Espanhol | LILACS | ID: biblio-831014

RESUMO

La agricultura orgánica es una forma activa de trabajo ecológico, que se produce bajo un conjunto de procedimientos denominados “orgánicos”, teniendo el productor bajo su responsabilidad un territorio al que debe liberar de toda contaminación y preocuparse por estimular la diversidad de especies, protegiendo la fauna. Dichos procedimientos tienen como objetivo principal la obtención de alimentos más saludables y la protección del medio ambiente por medio del uso de técnicas no contaminantes, además de disminuir el uso de energía y de sustancias inorgánicas, sobre todo si son de origen sintético.


Assuntos
Humanos , Alimentos Orgânicos , Ciências da Nutrição , Agricultura Orgânica
5.
Environ Res ; 132: 197-205, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24813577

RESUMO

Juveniles of Solea senegalensis were fed with commercial pellets under controlled conditions at two environmental Mediterranean temperatures (15 and 20°C) for two months. After this period, the accumulation of essential and non-essential metals and metallothionein (MT) levels was measured in liver and kidney by inductively coupled plasma mass spectrometry (ICP-MS) and pulse polarography, respectively. The bioaccumulation factor (BAF) for selected metals in both tissues was calculated in relation to levels present in the feed. Tissue partitioning (liver/kidney) and molar ratios, considering the metal protective mechanisms: MT and Selenium (Se), were included for evaluating the detoxification capacity of each tissue. Ag, Cd, Cu and Mn were preferentially accumulated in the liver whereas Co, Fe, Hg, Se and Zn were found in larger concentrations in the kidney, and higher temperature enhanced the accumulation of some of them, but not all. MT content in liver, but not in kidney, was also influenced by temperature changes and by length of exposure. The BAF revealed that Cu was taken up mainly by the liver whereas Se was efficiently taken up by both tissues. The high molar ratios of MT and most metals denoted the kidney's remarkable spare capacity for metal detoxification through MT binding. Moreover, the potential protective role of Se was also more evident in kidney as a higher Se:Cd and Se:Ag molar ratios were reached in this organ. In contrast to other fish, the storage of Cd in kidney was particularly low.


Assuntos
Aclimatação , Linguados/metabolismo , Rim/metabolismo , Fígado/metabolismo , Metalotioneína/metabolismo , Metais/metabolismo , Animais , Análise de Alimentos , Temperatura
6.
Mar Pollut Bull ; 77(1-2): 90-9, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24215996

RESUMO

The common sole, Solea solea and the Senegalese sole, Solea senegalensis are two important commercial species that coexist in the NW Mediterranean Sea. The present field survey was designed to assess the role of kidney in metal handling and detoxification in the two sole species collected at six fishing grounds along the Catalan coast. Metallothionein (MT) and selenium (Se) were analysed in relation to toxic metal loads in kidney as potential protective mechanisms. Acetylcholinesterase (AChE) and lactate dehydrogenase (LDH) activities as well as lipid peroxidation (LP) levels were measured in several tissues as general markers of toxicity. AChE was measured in brain muscle and gills, LDH in plasma and LP in muscle and gills. The protective role of MT and Se was indicated by the positive correlations with Hg and Cd levels as well as with the high Se:Hg ratio, in a species-dependent way. Principal Component Analysis (PCA) considering all chemical and biomarker variables discriminated individuals collected at the different fishing grounds.


Assuntos
Monitoramento Ambiental , Linguados/metabolismo , Metais/metabolismo , Poluentes Químicos da Água/metabolismo , Acetilcolinesterase/metabolismo , Animais , Biomarcadores/metabolismo , Pesqueiros , Brânquias/metabolismo , Inativação Metabólica , L-Lactato Desidrogenase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Mar Mediterrâneo , Metalotioneína/metabolismo , Músculos/metabolismo
7.
BMJ Open ; 3(6)2013 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-23794585

RESUMO

OBJECTIVES: To determine the prevalence of anorectal Chlamydia trachomatis serovars in a group of men who have sex with men (MSM) with high risk sexual behaviour, attendees at a sexually transmitted infection (STI) unit from a region in Northwest Spain. DESIGN: Retrospective and descriptive study of all swabs obtained from all MSM attendees at an STI unit, from 2007 to 2011. Retrospective ethical approval was granted by the Ethical Regional Committee of Clinical Investigation of the Principality of Asturias. SETTING: The STI clinic in Oviedo, Spain, offers screening and free-of-charge treatment to about 3646 patients per year. PARTICIPANTS: 303 symptomatic and asymptomatic consecutive and unselected MSM patients (mean age 36.7 and range 21-55 years) were evaluated for anorectal chlamydial infection. MAIN OUTCOME MEASURES: C trachomatis DNA extraction and detection in all rectal and in 36 urethral swabs. Characterisation of C trachomatis genotypes through sequencing of ompA gene amplicons and further phylogenetic tree analysis. RESULTS: We found 40 (13. 2%) positive rectal samples. The distribution of genotypes was E (37. 5%) followed by G (25%), D (12. 5%), J (10%) and L2b (5%).25 (62.5%, 95% CI 46.2 to 78.7) of the chlamydia-infected MSM showed clinical manifestations while 15 (37.5%, 95% CI 21.25 to 53.75) reported no symptoms. Concurrent infection with other STIs was documented in 27 (67.5%, 95% CI 51.7 to 83.2) patients. The most frequently reported clinical symptom was anal ulcer (7 cases, 17.5%; 95% CI 4.47 to 30.52). E genotype was mostly detected in asymptomatic patients. There were non-E genotypes detected in 21 (84%, 95% CI 63.9 to 95.5) of 25 symptomatic patients (p<0.001). CONCLUSIONS: The first two confirmed cases of lymphogranuloma venereum (LGV) in MSM in Asturias are reported, probably indicating the increase of this infection. The Spanish C trachomatis laboratory-based surveillance system may underlie an underestimated number of chlamydial infections. Whenever mild and atypical symptoms exist, laboratory evaluation would contribute to the early implementation of appropriate therapy and prevent LGV dissemination.

8.
Chemosphere ; 80(5): 570-7, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20451238

RESUMO

Gilthead sea bream Sparus aurata is the most commercialized Mediterranean aquacultured fish species. Ivermectin has recently (experimentally) started to be used to control ectoparasitic infestations in Mediterranean cultured marine fish. The potential hepatotoxicity of ivermectin was investigated in gilthead sea bream juveniles (35g) following oral administration at the recommended dose of 0.2 mgkg(-1) fish for 10d. Difference Gel Electrophoresis Technology (DIGE) was used to study the effect of this treatment in gilthead sea bream liver protein profile under routine culture conditions. The 2D-DIGE protein maps obtained were analyzed using the DeCyder 6.5 software. The results obtained showed significant changes in the expression of 36 proteins respect to the control group. Among these proteins, six increased in abundance, and 30 decreased. Spot showing differential expression respect to the control were analyzed by mass spectrometry and database search, which resulted in three positive identifications corresponding to hepatic proteins involved in lipid metabolism (apoA-I), oxidative stress responses and energy generation (beta-globin, ATP synthase subunit beta). These proteins have not been previously associated to invermectin effect.


Assuntos
Antiparasitários/toxicidade , Proteínas de Peixes/metabolismo , Ivermectina/toxicidade , Fígado/efeitos dos fármacos , Proteoma/metabolismo , Dourada/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Fígado/metabolismo
9.
Sci Total Environ ; 398(1-3): 48-52, 2008 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-18420254

RESUMO

The sublethal zinc toxicity to Artemia parthenogenetica as regards the possibility of colonization of zinc polluted salterns by means of cysts has been assessed by a cyst hatching assay and a life table approach. Emergence and hatching at different times as well as the whole hatching profile were taken as end-points for evaluating success of development. Demographic and reproductive parameters calculated according to the Lotka equation were used as an indicator of the chronic toxicity of the population. No adverse effects of waterborne zinc were found on hatching and emergence of cysts of A. parthenogenetica at any of the concentrations tested (0.01 mg/l, 0.1 mg/l, 0.5 mg/l, 1 mg/l, 5 mg/l). Chronic zinc exposure at 0.08 mg/l had detrimental effects on A. parthenogenetica fecundity, as detected by a decrease in the percentage of fertile females, which in turn produces a decrease in r. Chronic toxicity of zinc may be a limiting step for A. parthenogenetica colonization and the establishing of permanent populations in zinc-polluted brine ponds.


Assuntos
Artemia/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Zinco/toxicidade , Animais , Artemia/fisiologia , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Crescimento Demográfico , Reprodução/efeitos dos fármacos
10.
Environ Int ; 33(4): 532-9, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17157913

RESUMO

Metallothionein and metal content (Cd, Zn, Hg, Cu, Fe, Pb and Mn) were determined in various organs of commercially available eel (Anguilla anguilla) of similar size obtained from a local farm and from The Albufera Lake in Valencia (Spain). Farmed fish showed statistically significant higher Cd concentrations in liver and kidney whereas wild individuals had higher levels of Pb in blood and Zn in kidney. Significant positive correlations were found between metallothionein and Cd in kidney of farmed eel and between metallothionein and Cu in liver of wild ones. No statistically significant differences were found between the two populations in the concentration of any of the metals analyzed in muscle and in all instances these levels were lower than the limits established by the Spanish legislation for fish destined for human consumption.


Assuntos
Aquicultura , Enguias , Metalotioneína/análise , Metais/análise , Animais , Guias como Assunto
11.
Arch Environ Contam Toxicol ; 50(1): 111-20, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16237493

RESUMO

The toxicokinetics of cadmium was determined for five populations belonging to four species of Artemia (A. salina, A. parthenogenetica, A. franciscana, and A. persimilis) using a bicompartmental model. The effects of sublethal cadmium concentration on the kinetic parameters in A. parthenogenetica were determined. The BCF values are inversely related to the concentration, as is the uptake rate (ku), whilst the elimination rate (ke) constant seems to be directly related to the exposure concentration. Values corresponding to the rate of metal influx (I) remain relatively constant (0.2477 to 0.4455 microg/g.h) in the concentration range from 0.1 to 1 mg Cd/L, and are higher (1.098 microg/g.h) at an exposure to 10 mg Cd/L. The cadmium accumulation pattern seems well conserved in the genus and is characterized by a fast elimination of the metal with Ke ranging from 0.0050 to 0.0231 h(-1). A. persimilis displays a different model to that corresponding to the other studied species exposed to the same cadmium concentration, presenting a low uptake rate constant (1.0564 mL/g. h) and a low BCF (211.3 mL/g).


Assuntos
Artemia/metabolismo , Cádmio/farmacocinética , Cádmio/toxicidade , Poluentes da Água/farmacocinética , Poluentes da Água/toxicidade , Animais , Artemia/classificação , Artemia/efeitos dos fármacos , Artemia/crescimento & desenvolvimento , Modelos Biológicos
12.
Eur J Pharmacol ; 270(4): 361-4, 1994 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-7805786

RESUMO

Exposure of cultured cerebellar neurons to the putative metabotropic glutamate receptor antagonist L-2-amino-3-phosphonopropionate (L-AP3) for 24 h produced a neurotoxic effect which was prevented by the addition of the NMDA receptor antagonist (+)-10,11-dihydro-5-methyl-5-H-dibenzo-[a,d]-cyclohepten-5,1 0-imine hydrogen maleate (MK-801). MK-801 did also reduce neurotoxicity following 72 h exposure to L-AP3 neurotoxicity in the presence of MK-801 was antagonized by glutamate. Our results suggest that metabotropic glutamate receptors may play an important role in neuronal survival by controlling NMDA receptor-dependent as well as independent pathways.


Assuntos
Alanina/análogos & derivados , Cerebelo/citologia , Neurônios/efeitos dos fármacos , Receptores de Glutamato Metabotrópico/antagonistas & inibidores , 6-Ciano-7-nitroquinoxalina-2,3-diona/farmacologia , Alanina/toxicidade , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cerebelo/efeitos dos fármacos , Maleato de Dizocilpina/farmacologia , Ratos , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores
15.
Artigo em Inglês | MEDLINE | ID: mdl-1358538

RESUMO

1. The changes in the biochemical composition of gills, hepatopancreas and muscle after exposure to 0.25 mg Hg/l were studied in Procambarus clarkii. 2. Sublethal exposure to mercury in P. clarkii resulted in significant decreases in protein concentration and caloric concentration in gills over the 96 hr period. Glycogen/lipid and glycogen/protein ratios increased after 48 and 96 hr of mercury exposure. 3. Lipid and caloric concentration in the hepatopancreas were significantly lower in 96 hr mercury exposed group. 4. Glycogen concentration in muscle was depleted as consequence of 96 hr mercury exposure.


Assuntos
Brânquias/efeitos dos fármacos , Fígado/efeitos dos fármacos , Mercúrio/toxicidade , Músculos/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Animais , Astacoidea , Relação Dose-Resposta a Droga , Feminino , Brânquias/química , Dose Letal Mediana , Fígado/química , Masculino , Músculos/química , Pâncreas/química
16.
Brain Res ; 577(1): 41-8, 1992 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-1355695

RESUMO

In 1987, an intoxication by cultured mussels produced neurological problems, such as headache, confusion, and loss of memory, particularly severe at times. Neuronal damage was found in the hippocampus and amygdala of four patients. The intoxication was attributed to the presence in mussels of domoic acid, a rare excitatory amino acid acting at the non-NMDA receptor. We now report that a domoic acid-containing mussel extract is more neurotoxic for cultured neurons than purified domoic acid. Moreover, we show that this increase in neurotoxicity is selectively due to domoic acid potentiation of the excitotoxic effect of glutamic acid and aspartic acid present in high concentrations in mussel tissue. We also show that subtoxic concentrations of domoic acid are sufficient to potentiate glutamic acid and aspartic acid neurotoxicity, and we present evidence suggesting that the neurotoxic synergism may occur through a reduction of the voltage-dependent Mg2+ block at the NMDA receptor-associated channel, following activation of non-NMDA receptors by domoic acid. Thus, based on our results, we suggest that the contemporary presence in the brain of concentrations of domoic acid insufficient alone to be toxic, together with excitatory amino acids, of endogenous and eventually of diet-related origin, may have been relevant in the occurrence of the neurological problems reported.


Assuntos
Aminoácidos/farmacologia , Bivalves/química , Ácido Caínico/análogos & derivados , Toxinas Marinhas/toxicidade , Neurônios/efeitos dos fármacos , Neurotoxinas/toxicidade , Animais , Ácido Aspártico/farmacologia , Células Cultivadas , Sinergismo Farmacológico , Glutamatos/farmacologia , Ácido Glutâmico , Ácido Caínico/análise , Ácido Caínico/toxicidade , Toxinas Marinhas/análise , Neurotoxinas/análise , Ratos , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos
17.
Toxicology ; 72(2): 167-74, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1566278

RESUMO

Isolated trophoblast cells from human placenta at term were used to investigate the effect of cadmium exposure on the placental transport of zinc. Cells were exposed to cadmium acetate (0-2 microM) for 18 h. These concentrations were found to be non-cytotoxic as determined by protein recovery and the leakage of lactate dehydrogenase. Primary trophoblast cultures showed a cadmium-dependent increase in metallothionein content. After incubation with 65Zn for different times 65Zn contents were compared between control and cadmium-exposed cells. Zinc uptake by the cells after cadmium pre-exposure was increased in a cadmium dose-dependent manner. The additional amount of zinc that was taken up by the cadmium pre-exposed cells with respect to the control cells remained constant during a 30-min incubation of the same cells in a metal-free medium. The cytosol of cadmium-exposed cells showed a higher content of zinc than that of control cells. Most of the zinc in the cytosol is in the metallothionein fraction. We have thus demonstrated that cadmium-induced metallothionein binds zinc in the trophoblast, making this essential element less available to the fetal circulation.


Assuntos
Cádmio/farmacologia , Metalotioneína/biossíntese , Placenta/efeitos dos fármacos , Zinco/metabolismo , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/metabolismo , Cromatografia em Gel , Feminino , Humanos , L-Lactato Desidrogenase/metabolismo , Metalotioneína/metabolismo , Placenta/enzimologia , Placenta/metabolismo
18.
Amino Acids ; 2(3): 233-44, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24192902

RESUMO

A recent episode of human intoxication by cultured mussels containing a rare excitatory amino acid named domoic acid, received particular attention for its neurological implications. The intoxication produced neurological problems, such as headache, confusion, and loss of memory, particularly severe at times. Neuronal damage was found in the hippocampus and amygdala of four patients. We now report that in neuronal cultures the neurotoxicity of a domoic acid-containing mussel extract is the result of domoic acid potentiation of the excitotoxic effect of glutamic acid and aspartic acid present in high amounts in mussel tissue. Moreover, we show that subtoxic concentrations of domoic acid are sufficient to potentiate glutamic acid and aspartic acid neurotoxicity. We present evidence suggesting that the neurotoxic synergism may be due to a reduction of Mg(+ +) block at the NMDA receptor-associated channel, following activation of NON-NMDA receptors by domoic acid.

20.
Biol Trace Elem Res ; 21: 343-7, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2484611

RESUMO

Intermolt adult crayfish P. clarkii were used for this work. After acclimatization to laboratory conditions crayfish were exposed to sublethal concentrations of cadmium, mercury, and lead for 96 h. Gills of control and exposed crayfish were removed and ATPase activity and oxygen uptake rate were determined. Structural damage of gill filaments was also observed. Gill tissue respiration rates were measured for individual crayfish using a Gilson differential respirometer. Lead causes a decrease of gill oxygen uptake, but neither cadmium nor mercury seems to affect it at the concentrations employed. Although all metals studied alter gill filament structure, lead damage is the most apparent. In the same way, significant differences in gill ATPase activity owing to metal exposure were only observed in lead treated crayfish.


Assuntos
Astacoidea/metabolismo , Cádmio/toxicidade , Brânquias/metabolismo , Chumbo/toxicidade , Mercúrio/toxicidade , Animais , ATPase de Ca(2+) e Mg(2+)/antagonistas & inibidores , ATPase de Ca(2+) e Mg(2+)/metabolismo , Brânquias/enzimologia , Consumo de Oxigênio/efeitos dos fármacos , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , ATPase Trocadora de Sódio-Potássio/metabolismo
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