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Abstract(s)
O TBT ganhou ampla aplicação como biocida em tintas anti vegetativas para navios. Este composto é extremamente tóxico para uma grande variedade de organismos, desde bactérias a mamíferos, incluídos os humanos. Recentemente a toxicidade do TBT tem sido demonstrada a nível vascular, e os resultados obtidos até ao momento parecem sugerir que o TBT pode constituir um fator de risco para a doença cardiovascular.
Desta forma, o objetivo principal deste trabalho foi averiguar os efeitos do TBT a nível vascular.
Através dos resultados verificou-se que uma exposição ao composto, a curto prazo, provoca nas HUA um efeito relaxante e dependente da concentração na presença dos agentes contrateis histamina e KCl.
Como resultados da exposição a longo prazo verificou-se que a maioria das artérias incubadas com 100 µM de TBT, aquando a adição de 5-HT, não têm capacidade de contrair e analisando o nível de expressão do gene 5-HT2A, este encontra-se sub-regulado. Para a histamina verificou-se que o composto induz uma relaxação dependente da concentração. Analisando os níveis de expressão do mRNA do H1 deparamo-nos com expressão génica reduzida.
Testes de viabilidade celular demonstram que a toxicidade do TBT para as HUASMC ocorre a partir da concentração de 1 µM.
Over the years, the TBT has gained a wide application as a biocide in antifouling paints for marine vessels. This compound is extremely toxic to an extensive range of organisms, from bacteria to mammals, including humans. Recently, TBT toxicity has been demonstrated in a vascular level, and the results obtained so far seem to suggest that TBT may constitute a risk factor for cardiovascular disease. There so, the main purpose of this current work was to verify TBT effects at a vascular level. Through the obtained results it was demonstrated that an exposure to the compound, at short term, induces concentration-dependent relaxation effect in the HUA in the presence of contractile agents, histamine and KCl. As results of the long term exposure to the compound was demonstrated, the majority of the incubated arteries with 100 µM of TBT, when 5-HT is added, do not have contraction capacity, and analyzing the 5-HT2A gene expression levels, showed that they are down-regulated. Regarding the histamine, it was demonstrated that the compound induces a concentration-dependent relaxation. The H1 gene expression levels showed lack of regulation. Viability tests demonstrated that toxicity of TBT to HUASMC occurs from concentrations of 1 µM.
Over the years, the TBT has gained a wide application as a biocide in antifouling paints for marine vessels. This compound is extremely toxic to an extensive range of organisms, from bacteria to mammals, including humans. Recently, TBT toxicity has been demonstrated in a vascular level, and the results obtained so far seem to suggest that TBT may constitute a risk factor for cardiovascular disease. There so, the main purpose of this current work was to verify TBT effects at a vascular level. Through the obtained results it was demonstrated that an exposure to the compound, at short term, induces concentration-dependent relaxation effect in the HUA in the presence of contractile agents, histamine and KCl. As results of the long term exposure to the compound was demonstrated, the majority of the incubated arteries with 100 µM of TBT, when 5-HT is added, do not have contraction capacity, and analyzing the 5-HT2A gene expression levels, showed that they are down-regulated. Regarding the histamine, it was demonstrated that the compound induces a concentration-dependent relaxation. The H1 gene expression levels showed lack of regulation. Viability tests demonstrated that toxicity of TBT to HUASMC occurs from concentrations of 1 µM.
Description
Keywords
Artéria Umbilical Humana Banho de Órgãos Disruptores Endócrinos Organoestanhos Qpcr. Tbt