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1.
Environ Manage ; 65(5): 575-586, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32107570

RESUMO

Understanding and communicating the links among human activities and marine ecosystem services are fundamental for ecosystem-based management, which aims at attaining ecological, economic and social sustainability in the use of our seas. Relationships are typically complex and may differ between geographic areas. Here, an assessment model that combines available quantitative, semi-quantitative and qualitative information, rooted in the DAPSIR (Driver-Activity-Pressure-State-Impact-Response) framework and assessment requirements of the EU Marine Strategy Framework Directive, is developed and applied. Focusing on Swedish marine waters, major human activities at sea are evaluated in relation to their dependencies and impacts on the status of marine ecosystem services. This case study is a consensus assessment based on evaluation of available literature and data. By relating degrees of dependencies and impacts to values of different economic sectors, discrepancies among sectors with respect to their impact versus their monetary value can be identified. In our case, commercial fishing depends on and influences a wide range of ecosystem services, while other sectors, such as shipping, depend little on marine ecosystem services. At the extreme end of the range, pressures from human activities in the past, such as historical nutrient emissions, still have prominent influence on ecosystem services today, entailing considerable losses. Marine tourism and commercial fishing show similar dependencies on ecosystem services, but tourism has a clearly lower impact on ecosystem services and a higher monetary value. The model may serve as a useful tool for communicating and guiding priorities in integrated environmental management and maritime spatial planning.


Assuntos
Ecossistema , Atividades Humanas , Conservação dos Recursos Naturais , Pesqueiros , Humanos , Oceanos e Mares
2.
Bioorg Med Chem Lett ; 24(1): 108-12, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24332486

RESUMO

A series of fused bicyclic and urea derivatives of spirocyclic compounds were designed, synthesised and evaluated in vitro as potent CCR1 antagonists. In particular, 4 (7nM), 44 (1.3nM), 48 (0.89nM) and 50 (0.63nM) were the most potent hCCR1 antagonists in this series of compounds. Moreover, some of these substances demonstrated good rodent cross-over, especially 46 which exhibited very high rat CCR1 binding affinity with an IC50 value of 16nM.


Assuntos
Compostos Bicíclicos com Pontes/química , Receptores CCR1/antagonistas & inibidores , Compostos de Espiro/farmacologia , Ureia/química , Animais , Relação Dose-Resposta a Droga , Estrutura Molecular , Ratos , Compostos de Espiro/síntese química , Compostos de Espiro/química , Relação Estrutura-Atividade , Ureia/análogos & derivados
3.
Ambio ; 53(1): 109-125, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37542612

RESUMO

Interest in coastal restoration measures is increasing, but information about subsequent ecosystem recovery processes is limited. In Björnöfjärden on the Baltic Sea coast, Stockholm archipelago, a pioneering case study to reduce coastal eutrophication led to improvements and initially halved phosphorus levels. Here, we evaluate the effects of the restoration on the local fish assemblage over one decade after the measures. The study gives a unique possibility to evaluate responses of coastal fish to nutrient variables and abatement in a controlled natural setting. Cyprinid abundance decreased and perch partially increased with decreasing turbidity levels, while mean trophic level increased over time in the restored area. Responses were overall weak, likely attributed to an attenuation of the eutrophication abatement effect over time. The results suggest that nutrient reduction gives slow responses in fish compared to alternative measures such as fishing closures.


Assuntos
Baías , Ecossistema , Animais , Fósforo , Eutrofização , Países Bálticos , Nitrogênio/análise
4.
Bioorg Med Chem Lett ; 23(14): 4026-30, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23769642

RESUMO

A series of zwitterionic spirocyclic compounds were synthesised. In vitro data revealed that these compounds were potent CCR1 antagonists. In particular, 2, 4, 11 and 20 inhibited CCR1 mediated chemotaxis of THP-1 cells in a functional assay.


Assuntos
Desenho de Fármacos , Receptores CCR1/antagonistas & inibidores , Compostos de Espiro/química , Linhagem Celular Tumoral , Quimiotaxia/efeitos dos fármacos , Humanos , Ligação Proteica , Receptores CCR1/metabolismo , Compostos de Espiro/síntese química , Compostos de Espiro/farmacologia , Relação Estrutura-Atividade
5.
Ambio ; 52(3): 556-570, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36324024

RESUMO

Establishment of artificial reefs and no-take areas are management measures available for restoring deteriorated marine ecosystems, compensating for habitat loss and strengthening harvested populations. Following the establishment of no-take artificial reefs in western Sweden to compensate for hard bottoms lost to a shipping lane, we detected rapid positive effects on crustaceans and demersal fish compared to fished reference areas. The relative abundance and size structure of European lobster (Homarus gammarus) increased strongly in the no-take area indicating more than doubled and tripled egg production in 5 and 10 years, respectively. For benthic fish and crustacean communities, the abundances of gadoids and wrasses increased and the abundances of small decapod crustaceans decreased in the no-take area, likely indicating cascading effects of increased predation. The study demonstrates that relatively small no-take areas, enhanced by artificial reefs, can rapidly invigorate populations of lobster and fish that in turn may re-initiate local top-down control.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Peixes , Suécia , Nephropidae
6.
Ambio ; 50(7): 1325-1336, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33507497

RESUMO

Marine ecosystems are under high demand for human use, giving concerns about how pressures from human activities may affect their structure, function, and status. In Europe, recent developments in mapping of marine habitats and human activities now enable a coherent spatial evaluation of potential combined effects of human activities. Results indicate that combined effects from multiple human pressures are spread to 96% of the European marine area, and more specifically that combined effects from physical disturbance are spread to 86% of the coastal area and 46% of the shelf area. We compare our approach with corresponding assessments at other spatial scales and validate our results with European-scale status assessments for coastal waters. Uncertainties and development points are identified. Still, the results suggest that Europe's seas are widely disturbed, indicating potential discrepancy between ambitions for Blue Growth and the objective of achieving good environmental status within the Marine Strategy Framework Directive.


Assuntos
Ecossistema , Atividades Humanas , Conservação dos Recursos Naturais , Monitoramento Ambiental , Europa (Continente) , Humanos , Oceanos e Mares
7.
Ambio ; 49(5): 1090-1099, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31598833

RESUMO

Improving water clarity is a core objective for eutrophication management in the Baltic Sea, but may influence fisheries via effects on fish habitat suitability. We apply an ensemble of species distribution models coupled with habitat productivity functions and willingness-to-pay estimates to assess these effects for two coastal predatory fish species, European perch (Perca fluviatilis) and pikeperch (Sander lucioperca). The models predicted a 37% increase in perch and 59% decrease in pikeperch biomass if reaching the reference level for water clarity in the Baltic Sea Action Plan. Reaching the target level was predicted to increase perch biomass by 13%. However, the associated economic gain for the recreational fisheries sector was countervailed by an 18% pikeperch reduction. Still, a net benefit was predicted since there are six times more fishing days for perch than pikeperch. We exemplify how ecological modelling can be combined with economic analyses to map and evaluate management alternatives.


Assuntos
Eutrofização , Pesqueiros , Animais , Países Bálticos , Biomassa , Ecossistema
8.
Ambio ; 49(2): 391-406, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31168701

RESUMO

Declining physiological status in marine top consumers has been observed worldwide. We investigate changes in the physiological status and population/community traits of six consumer species/groups in the Baltic Sea (1993-2014), spanning four trophic levels and using metrics currently operational or proposed as indicators of food-web status. We ask whether the physiological status of consumers can be explained by food-web structure and prey food value. This was tested using partial least square regressions with status metrics for gray seal, cod, herring, sprat and the benthic predatory isopod Saduria as response variables, and abundance and food value of their prey, abundance of competitors and predators as predictors. We find evidence that the physiological status of cod, herring and sprat is influenced by competition, predation, and prey availability; herring and sprat status also by prey size. Our study highlights the need for management approaches that account for species interactions across multiple trophic levels.


Assuntos
Cadeia Alimentar , Comportamento Predatório , Animais , Países Bálticos , Peixes , Alimentos Marinhos
9.
Sci Total Environ ; 709: 136144, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-31905569

RESUMO

Eutrophication is a serious threat to aquatic ecosystems globally with pronounced negative effects in the Baltic and other semi-enclosed estuaries and regional seas, where algal growth associated with excess nutrients causes widespread oxygen free "dead zones" and other threats to sustainability. Decades of policy initiatives to reduce external (land-based and atmospheric) nutrient loads have so far failed to control Baltic Sea eutrophication, which is compounded by significant internal release of legacy phosphorus (P) and biological nitrogen (N) fixation. Farming and harvesting of the native mussel species (Mytilus edulis/trossulus) is a promising internal measure for eutrophication control in the brackish Baltic Sea. Mussels from the more saline outer Baltic had higher N and P content than those from either the inner or central Baltic. Despite their relatively low nutrient content, harvesting farmed mussels from the central Baltic can be a cost-effective complement to land-based measures needed to reach eutrophication status targets and is an important contributor to circularity. Cost effectiveness of nutrient removal is more dependent on farm type than mussel nutrient content, suggesting the need for additional development of farm technology. Furthermore, current regulations are not sufficiently conducive to implementation of internal measures, and may constitute a bottleneck for reaching eutrophication status targets in the Baltic Sea and elsewhere.


Assuntos
Bivalves , Agricultura , Animais , Países Bálticos , Eutrofização , Nitrogênio , Oceanos e Mares , Fósforo
10.
BMC Evol Biol ; 9: 70, 2009 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-19335884

RESUMO

BACKGROUND: Theory predicts that speciation can be quite rapid. Previous examples comprise a wide range of organisms such as sockeye salmon, polyploid hybrid plants, fruit flies and cichlid fishes. However, few studies have shown natural examples of rapid evolution giving rise to new species in marine environments. RESULTS: Using microsatellite markers, we show the evolution of a new species of brown macroalga (Fucus radicans) in the Baltic Sea in the last 400 years, well after the formation of this brackish water body ~8-10 thousand years ago. Sympatric individuals of F. radicans and F. vesiculosus (bladder wrack) show significant reproductive isolation. Fucus radicans, which is endemic to the Baltic, is most closely related to Baltic Sea F. vesiculosus among north Atlantic populations, supporting the hypothesis of a recent divergence. Fucus radicans exhibits considerable clonal reproduction, probably induced by the extreme conditions of the Baltic. This reproductive mode is likely to have facilitated the rapid foundation of the new taxon. CONCLUSION: This study represents an unparalleled example of rapid speciation in a species-poor open marine ecosystem and highlights the importance of increasing our understanding on the role of these habitats in species formation. This observation also challenges presumptions that rapid speciation takes place only in hybrid plants or in relatively confined geographical places such as postglacial or crater lakes, oceanic islands or rivers.


Assuntos
Fucus/genética , Especiação Genética , Filogenia , Teorema de Bayes , DNA de Algas/genética , Ecossistema , Fucus/classificação , Frequência do Gene , Variação Genética , Genética Populacional , Geografia , Repetições de Microssatélites , Oceanos e Mares , Reprodução Assexuada , Especificidade da Espécie
11.
Ambio ; 48(6): 565-579, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30523568

RESUMO

Understanding the relative impacts of pressures on coastal ecosystems is central for implementing relevant measures to reach environmental management objectives. Here, survey data on the species and size composition of coastal fish are evaluated in relation to fishing and eutrophication, by comparing a long-standing no-take area to an environmental gradient in the Baltic Sea. The no-take area represents an intermediate eutrophication level, but the species composition resembles that seen at low eutrophication in areas with fishing. The catch biomass of piscivores is 2-3 times higher in the no-take area than in the other areas, while the biomass of Cyprinids, generally benefitted by eutrophication, corresponds to that of areas with low eutrophication. The results support that fishing may generate eutrophication-like effects, and, conversely, that no-take areas may contribute to improving environmental status in impacted areas by enhancing piscivores, which in turn may contribute to further improvement in the food web.


Assuntos
Ecossistema , Eutrofização , Animais , Países Bálticos , Biomassa , Monitoramento Ambiental , Cadeia Alimentar
12.
Brain Res ; 1219: 103-10, 2008 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-18539264

RESUMO

Anabolic androgenic steroids (AAS) are known as doping agents within sports and body-building, but are currently also abused by other groups in society in order to promote increased courage and aggression. We previously showed that 14 days of daily intramuscular injections of the AAS nandrolone decanoate (15 mg/kg) reduced the extracellular levels of the dopaminergic metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the nucleus accumbens shell using microdialysis. The aim of the present study was to investigate whether the same dose regimen of nandrolone decanoate may affect the activities of the dopamine-metabolizing enzymes monoamine oxidases A and B (MAO-A and MAO-B). A radiometric assay was used to determine the activities of MAO-A and MAO-B in rat brain tissues after 14 days of daily i.m. nandrolone decanoate injections at the doses 3 and 15 mg/kg. Gene transcript contents of MAO-A, MAO-B and cathecol-O-methyltransferase (COMT) were measured with quantitative real-time reverse transcription PCR. 3 mg/kg of nandrolone decanoate significantly reduced the activity of both MAO-A and -B in the caudate putamen. 15 mg/kg of nandrolone decanoate significantly reduced the activity of MAO-A in the amygdala and increased the gene transcript level of MAO-B in the substantia nigra. In conclusion, imbalanced MAO activities may contribute to explain the impulsive and aggressive behaviour often described in AAS abusers. The reduced MAO activities observed are in line with our previously presented findings of decreased extracellular levels of DOPAC and HVA in the rat brain, indicating decreased monoaminergic activity following repeated AAS administration.


Assuntos
Anabolizantes/administração & dosagem , Encéfalo/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Monoaminoxidase/metabolismo , Nandrolona/análogos & derivados , Análise de Variância , Animais , Encéfalo/enzimologia , Esquema de Medicação , Masculino , Monoaminoxidase/genética , Nandrolona/administração & dosagem , Decanoato de Nandrolona , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
13.
Neurosci Lett ; 412(2): 168-72, 2007 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-17123707

RESUMO

Associated with acts of violence and polydrug use, abuse of anabolic androgenic steroids (AAS) is an increasing problem in society. The aim of the present study was to elucidate whether sub-chronic treatment with the AAS nandrolone decanoate affects dopamine release and dopamine metabolism in the rat nucleus accumbens shell, before and after an amphetamine challenge. Male Sprague-Dawley rats received daily i.m. injections of nandrolone decanoate (15 mg/kg) or vehicle for 14 days. On day 15, the animals were anaesthetized and a microdialysis probe was implanted into the nucleus accumbens shell. Extracellular fluid was collected 1h before and 3h after a single amphetamine injection (5 mg/kg). The samples were then analyzed regarding the content of dopamine, and its metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), using HPLC with electrochemical detection. Two weeks of nandrolone decanoate administration caused a significant decrease of the basal DOPAC and HVA levels, which remained low during the first hour following the amphetamine challenge. Dopamine levels did not differ significantly between groups, neither after the nandrolone pre-treatment nor the amphetamine challenge. In conclusion, these novel findings indicate that AAS alter the metabolism of dopamine in a brain region involved in the development of drug dependence.


Assuntos
Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Anfetamina/farmacologia , Dopamina/metabolismo , Ácido Homovanílico/metabolismo , Nandrolona/farmacologia , Núcleo Accumbens/efeitos dos fármacos , Anabolizantes/farmacologia , Animais , Inibidores da Captação de Dopamina/farmacologia , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Interações Medicamentosas/fisiologia , Líquido Extracelular/efeitos dos fármacos , Líquido Extracelular/metabolismo , Masculino , Microdiálise , Núcleo Accumbens/metabolismo , Ratos , Ratos Sprague-Dawley , Transtornos Relacionados ao Uso de Substâncias/metabolismo , Transtornos Relacionados ao Uso de Substâncias/fisiopatologia , Fatores de Tempo
14.
Mar Pollut Bull ; 114(2): 664-670, 2017 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-27780582

RESUMO

Identifying the main sources of nutrient loading is a key factor for efficient mitigation of eutrophication. This study has investigated the pathways of external nutrient loading to 656 coastal water bodies along the entire Swedish coastline. The studied water bodies have been delineated to meet requirements in the European Union's Water Framework Directive, and recent status assessments have shown that 57% of them fail to attain good or high ecological status with respect to nutrients. The analysis in the study was performed on data from mass-balance based nutrient budgets computed using the modelling framework Vattenwebb. The external nutrient contribution from the sea to the water bodies was highly variable, ranging from about 1% to nearly 100%, but the median contribution was >99% of the total external loading regarding both nitrogen and phosphorus. External loading from the atmosphere and local catchment area played a minor role in general. However, 45 coastal water bodies received >25% of the external nitrogen and phosphorus from their catchments. Loading from land typically peaked in April following ice-break and snow melting and was comparatively low during summer. The results indicate that for many eutrophicated Swedish coastal water bodies, nutrient abatement is likely to be optimally effective when potential measures in all of the catchment area of the concerned sea basin are considered. Local-scale mitigation in single water bodies will likely be locally effective only in the small proportion of areas where water and thereby also nutrient input from the catchment is high compared to the influx from the sea. Future studies should include nutrient reduction scenarios in order to refine these conclusions and to identify relevant spatial scales for coastal eutrophication mitigation measures from a water body perspective.


Assuntos
Atmosfera/química , Monitoramento Ambiental/métodos , Nitrogênio/análise , Fósforo/análise , Água do Mar/química , Poluentes Químicos da Água/análise , Eutrofização , Modelos Teóricos , Oceanos e Mares , Estações do Ano , Suécia
15.
Mar Biol ; 163(10): 201, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27656003

RESUMO

Shallow nearshore habitats are highly valued for supporting marine ecosystems, but are subject to intense human-induced pressures. Mesopredatory fish are key components in coastal food webs, and alterations in their abundance may have evident effects also on other parts of the ecosystem. The aim of this study was to clarify the relationship between the abundance of coastal mesopredatory fish, defined as mid-trophic level demersal and benthic species with a diet consisting predominantly of invertebrates, and ambient environmental variables in a fjord system influenced by both eutrophication and overfishing. A field survey was conducted over a coastal gradient comprising 300 data points sampled consistently for fish community and environmental data. Results from multivariate and univariate analyses supported each other, demonstrating that mesopredatory fish abundance at species and functional group level was positively related to the cover of structurally complex vegetation and negatively related to eutrophication, as measured by water transparency. Contrary to other studies showing an inverse relationship to piscivore abundance over time, the spatial distribution of mesopredatory fish was not locally regulated by the abundance of piscivorous fish, probably attributed to piscivores being at historically low levels due to previous overfishing. Mesopredatory fish abundance was highest in areas with high habitat quality and positively related to the abundance of piscivores, suggesting a predominance of bottom-up processes. We conclude that, in parallel with ongoing regulations of fishing pressure, measures to restore habitat function and food web productivity are important for the recovery of coastal fish communities in the area.

16.
PLoS One ; 11(8): e0161266, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27525655

RESUMO

Closely related taxa provide significant case studies for understanding evolution of new species but may simultaneously challenge species identification and definition. In the Baltic Sea, two dominant and perennial brown algae share a very recent ancestry. Fucus vesiculosus invaded this recently formed postglacial sea 8000 years ago and shortly thereafter Fucus radicans diverged from this lineage as an endemic species. In the Baltic Sea both species reproduce sexually but also recruit fully fertile new individuals by asexual fragmentation. Earlier studies have shown local differences in morphology and genetics between the two taxa in the northern and western Bothnian Sea, and around the island of Saaremaa in Estonia, but geographic patterns seem in conflict with a single origin of F. radicans. To investigate the relationship between northern and Estonian distributions, we analysed the genetic variation using 9 microsatellite loci in populations from eastern Bothnian Sea, Archipelago Sea and the Gulf of Finland. These populations are located in between earlier studied populations. However, instead of bridging the disparate genetic gap between N-W Bothnian Sea and Estonia, as expected from a simple isolation-by-distance model, the new populations substantially increased overall genetic diversity and showed to be strongly divergent from the two earlier analysed regions, showing signs of additional distinct populations. Contrasting earlier findings of increased asexual recruitment in low salinity in the Bothnian Sea, we found high levels of sexual reproduction in some of the Gulf of Finland populations that inhabit extremely low salinity. The new data generated in this study supports the earlier conclusion of two reproductively isolated but very closely related species. However, the new results also add considerable genetic and morphological complexity within species. This makes species separation at geographic scales more demanding and suggests a need for more comprehensive approaches to further disentangle the intriguing relationship and history of the Baltic Sea fucoids.


Assuntos
Fucus/genética , Variação Genética , Oceanos e Mares , Europa (Continente) , Fucus/classificação , Frequência do Gene , Genótipo , Repetições de Microssatélites/genética , Salinidade
18.
Brain Res ; 986(1-2): 139-47, 2003 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-12965238

RESUMO

Supratherapeutical doses of anabolic androgenic steroids (AASs) have dramatic effects on metabolism in humans, and also inhibit feeding and reduce the rate of body weight gain in rats. In order to test the hypothesis that the AAS metabolic syndrome is accompanied by alterations in the central melanocortin system, we evaluated body weight, food intake and hypothalamic agouti-related protein (AgRP) and proopiomelanocortin (POMC) mRNA levels following administration of different doses of the anabolic androgenic steroid nandrolone decanoate. In order to distinguish changes induced by the steroid treatment per se from those resulting from the reduced food intake and growth rate, we also compared the effect of nandrolone decanoate on AgRP and POMC mRNA expression with both normally fed, and food restricted control groups. We here report that administration of nandrolone specifically reduces arcuate nucleus POMC mRNA levels while not affecting the expression level of AgRP. The effect on POMC expression was not observed in the food restricted controls, excluding the possibility that the observed effect was a mere response to the reduced food intake and body weight. These results raise the possibility that some of the metabolic and behavioural consequences of AAS abuse may be the result of alterations in the melanocortin system.


Assuntos
Regulação para Baixo/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Nandrolona/análogos & derivados , Nandrolona/farmacologia , Pró-Opiomelanocortina/genética , Proteínas/genética , Proteína Relacionada com Agouti , Animais , Núcleo Arqueado do Hipotálamo/efeitos dos fármacos , Núcleo Arqueado do Hipotálamo/metabolismo , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Relação Dose-Resposta a Droga , Regulação para Baixo/fisiologia , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Líquidos/fisiologia , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Alimentos/fisiologia , Privação de Alimentos/fisiologia , Hipotálamo/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular , Masculino , Decanoato de Nandrolona , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , alfa-MSH/metabolismo
19.
Neurosci Lett ; 361(1-3): 68-71, 2004 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-15135895

RESUMO

By use of the brain microdialysis technique we show that administration of gamma(1)-melanocyte stimulating hormone (gamma(1)-MSH) into the ventral tegmental area of anaesthetized rats causes an increase in the release of extracellular dopamine and its metabolite 3,4-dihydroxyphenylacetic acid in the nucleus accumbens, while gamma(2)-MSH causes the opposite effect. Moreover, gamma(2)-MSH pre-treatment considerably reduced the gamma(1)-MSH-induced effects. Our findings suggest an opposing action of two gamma-MSH-activated pathways on the mesolimbic dopaminergic system, which could be important in the maintenance of a balanced psychoactivation state.


Assuntos
Dopamina/metabolismo , Sistema Límbico/efeitos dos fármacos , Vias Neurais/efeitos dos fármacos , Núcleo Accumbens/efeitos dos fármacos , Área Tegmentar Ventral/efeitos dos fármacos , gama-MSH/farmacologia , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Química Encefálica/efeitos dos fármacos , Química Encefálica/fisiologia , Sistema Límbico/metabolismo , Masculino , Vias Neurais/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Núcleo Accumbens/metabolismo , Ratos , Ratos Sprague-Dawley , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/fisiologia , Área Tegmentar Ventral/metabolismo , gama-MSH/metabolismo
20.
PLoS One ; 8(5): e64767, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23737998

RESUMO

The structure of many marine ecosystems has changed substantially during recent decades, as a result of overexploitation, climate change and eutrophication. Despite of the apparent ecological and economical importance of coastal areas and communities, this aspect has received relatively little attention in coastal systems. Here we assess the temporal development of zoobenthos communities in two areas on the Swedish Baltic Sea coast during 30 years, and relate their development to changes in climate, eutrophication and top-down regulation from fish. Both communities show substantial structural changes, with a decrease in marine polychaetes and species sensitive to increased water temperatures. Concurrently, opportunistic species tolerant to environmental perturbation have increased in abundance. Species composition show a similar temporal development in both communities and significant changes in species composition occurred in both data sets in the late 1980s and early 1990s. The change in species composition was associated with large scale changes in climate (salinity and water temperature) and to the structure of the local fish community, whereas we found no effects of nutrient loading or ambient nutrient concentrations. Our results suggest that these coastal zoobenthos communities have gone through substantial structural changes over the last 30 years, resulting in communities of different species composition with potentially different ecological functions. We hence suggest that the temporal development of coastal zoobenthos communities should be assessed in light of prevailing climatic conditions considering the potential for top-down effects exerted by local fish communities.


Assuntos
Clima , Ecossistema , Oceanos e Mares , Animais , Biodiversidade , Meio Ambiente , Geografia , Modelos Teóricos , Análise Espaço-Temporal , Suécia
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