Long-term Mercury Exposure Accelerates the Development of Hypertension in Prehypertensive Spontaneously Hypertensive Rats Inducing Endothelial Dysfunction: the Role of Oxidative Stress and Cyclooxygenase-2.

Mercury is a metal widely dispersed in nature that when in contact with human organism, it damages the cardiovascular system. Long-term mercury exposure for 30 days induces endothelial dysfunction without blood pressure changes in normotensive adult rats. However, it is not known whether exposure to mercury can exacerbate endothelial dysfunction and hypertension development in predisposed animals. Thus, we aimed to investigate the effects of long-term mercury exposure on the blood pressure (BP) and in the isolated aortas of young normotensive and prehypertensive spontaneously hypertensive rats (SHRs). Four-week-old male Wistar rats and SHRs were treated daily with mercury chloride (HgCl2) (1st dose, 4.6 µg/kg; subsequent dose, 0.07 µg/kg/day, im, 30 days) or vehicle. BP was assessed weekly and the vascular reactivity to phenylephrine was evaluated in isolated aorta from rats exposed or not to mercury. Mercury exposure did not affect BP in young Wistar rats but accelerated the development of hypertension in young SHRs. Vascular reactivity to phenylephrine increased only in the aorta from mercury-exposed SHRs. While HgCl2 exposure in SHRs did not alter nitric oxide production, we observed increased superoxide anion production and decreased superoxide dismutase-1 protein expression, and enhanced cyclooxygenase-2 (COX-2) participation with increased prostaglandin (PGE2) production and decreased prostacyclin. In the Wistar group, mercury exposure did not alter superoxide anion production or the COX-2 pathway. Mercury exposure accelerated the natural course of hypertension in young SHRs and increased oxidative stress associated with reduced participation of antioxidant enzymes, an activated COX-2 pathway, thereby producing endothelial dysfunction, which is a risk factor in prehypertensive individuals.

STUDY OF THE ANTEROLATERAL LIGAMENT OF THE KNEE IN FORMALIN-EMBEDDED CADAVERS.

OBJECTIVE: To verify the incidence and characterize morphologically the anterolateral ligament of the knee (ALL) in cadaveric samples of the collection of the Laboratory of Anatomy of the Department of Morphology of the Universidade Federal do Espírito Santo. METHODS: Dissections and cross sections were performed for mesoscopic analysis of the anterolateral region of 15 knees preserved in 4% formalin solution in order to identify the ALL. RESULTS: After dissection of the skin and subcutaneous tissue of the knee anterolateral region, it was possible to identify the iliotibial tract (ITT), the patellar ligament and the femoral biceps tendon. The ITT was removed from the Gerdy tubercle and the following structures were visualized: knee joint capsule, fibular collateral ligament and popliteal tendon. However, the ALL was not identified in any of the samples. CONCLUSIONS: The ALL could not be identified in any of the specimens studied, either through dissection or mesoscopic analysis. Level of Evidence III, Diagnosis Studies - Investigation of an Exam for Diagnosis.

OBJETIVO: Verificar a incidência e possivelmente caracterizar morfologicamente o ligamento anterolateral do joelho (LAL) em amostras cadavéricas do acervo do Laboratório de Anatomia do Departamento de Morfologia da Universidade Federal do Espírito Santo. MÉTODOS: Foram realizadas dissecações e secções transversais para análise mesoscópica da região anterolateral de 15 joelhos conservados em solução de formalina a 4% a fim de identificar o LAL. RESULTADOS: Após a dissecação da pele e da tela subcutânea da região anterolateral dos joelhos foi possível identificar o trato iliotibial (TIT), o ligamento patelar e o tendão do músculo bíceps femoral. Após a desinserção do TIT no tubérculo de Gerdy as seguintes estruturas foram visualizadas: cápsula articular do joelho, o ligamento colateral fibular e o tendão do músculo poplíteo. Entretanto, o LAL não foi identificado em nenhuma das amostras. CONCLUSÕES: O LAL não pôde ser identificado em nenhum dos espécimes estudados, seja através da dissecação ou da análise mesoscópica. Nível de Evidência III, Estudos Diagnósticos - Investigação de um Exame para Diagnóstico.

STUDY OF THE ANTEROLATERAL LIGAMENT OF THE KNEE IN FORMALIN-EMBEDDED CADAVERS / ESTUDO DO LIGAMENTO ANTEROLATERAL DO JOELHO EM CADÁVERES FORMOLIZADOS

ABSTRACT Objective: To verify the incidence and characterize morphologically the anterolateral ligament of the knee (ALL) in cadaveric samples of the collection of the Laboratory of Anatomy of the Department of Morphology of the Universidade Federal do Espírito Santo. Methods: Dissections and cross sections were performed for mesoscopic analysis of the anterolateral region of 15 knees preserved in 4% formalin solution in order to identify the ALL. Results: After dissection of the skin and subcutaneous tissue of the knee anterolateral region, it was possible to identify the iliotibial tract (ITT), the patellar ligament and the femoral biceps tendon. The ITT was removed from the Gerdy tubercle and the following structures were visualized: knee joint capsule, fibular collateral ligament and popliteal tendon. However, the ALL was not identified in any of the samples. Conclusions: The ALL could not be identified in any of the specimens studied, either through dissection or mesoscopic analysis. Level of Evidence III, Diagnosis Studies - Investigation of an Exam for Diagnosis.

RESUMO Objetivo: Verificar a incidência e possivelmente caracterizar morfologicamente o ligamento anterolateral do joelho (LAL) em amostras cadavéricas do acervo do Laboratório de Anatomia do Departamento de Morfologia da Universidade Federal do Espírito Santo. Métodos: Foram realizadas dissecações e secções transversais para análise mesoscópica da região anterolateral de 15 joelhos conservados em solução de formalina a 4% a fim de identificar o LAL. Resultados: Após a dissecação da pele e da tela subcutânea da região anterolateral dos joelhos foi possível identificar o trato iliotibial (TIT), o ligamento patelar e o tendão do músculo bíceps femoral. Após a desinserção do TIT no tubérculo de Gerdy as seguintes estruturas foram visualizadas: cápsula articular do joelho, o ligamento colateral fibular e o tendão do músculo poplíteo. Entretanto, o LAL não foi identificado em nenhuma das amostras. Conclusões: O LAL não pôde ser identificado em nenhum dos espécimes estudados, seja através da dissecação ou da análise mesoscópica. Nível de Evidência III, Estudos Diagnósticos - Investigação de um Exame para Diagnóstico.