Enhanced expression of Ang-(1-7) during pregnancy

Pregnancy is a physiological condition characterized by a progressive increase of the different components of the renin-angiotensin system (RAS). The physiological consequences of the stimulated RAS in normal pregnancy are incompletely understood, and even less understood is the question of how this system may be altered and contribute to the hypertensive disorders of pregnancy. Findings from our group have provided novel insights into how the RAS may contribute to the physiological condition of pregnancy by showing that pregnancy increases the expression of both the vasodilator heptapeptide of the RAS, angiotensin-(1-7) [Ang-(1-7)], and of a newly cloned angiotensin converting enzyme (ACE) homolog, ACE2, that shows high catalytic efficiency for Ang II metabolism to Ang-(1-7). The discovery of ACE2 adds a new dimension to the complexity of the RAS by providing a new arm that may counter-regulate the activity of the vasoconstrictor component, while amplifying the vasodilator component. The studies reviewed in this article demonstrate that Ang-(1-7) increases in plasma and urine of normal pregnant women. In preeclamptic subjects we showed that plasma Ang-(1-7) was suppressed as compared to the levels found in normal pregnancy. In addition, kidney and urinary levels of Ang-(1-7) were increased in pregnant rats coinciding with the enhanced detection and expression of ACE2. These findings support the concept that in normal pregnancy enhanced ACE2 may counteract the elevation in tissue and circulating Ang II by increasing the rate of conversion to Ang-(1-7). These findings provide a basis for the physiological role of Ang-(1-7) and ACE2 during pregnancy.

Effect of angiotensin-(1-7) on reperfusion arrhythmias in isolated rat hearts

There is increasing evidence that angiotensin-(1-7) (Ang-(1-7) is an endogenous biologically active component of the renin-angiotensin system (RAS). In the present study, we investigated the effects of Ang-(1-7) on reperfusion arrhythmias in isolated rat hearts. Isolated rat hearts were perfused with two different media, i.e., Krebs-Ringer (2.52 mM CaCl2) and low-Ca2+ Krebs-Ringer (1.12 mM Cacl2) and low-Ca2+ Krebs-Ringer (1.12 mM CaCl2). In hearts perfused with Krebs-Ringer, Ang-(1-7) produced a concentration-dependent (27-210 nM) reduction in coronary flow (25 percent reduction at highest concentration), while only slight and variable changes in contaction force and heart rate were observed. Under the same conditions, angiotensin II (Ang II; 27 and 70 nM) produced a significant reduction in coronary flow (39 percent and 48 percent, respectively) associated with a significant increase in force. A decrease in heart rate was also observed. In low-Ca2+ Krebs-Ringer solution, perfusion with Ang-(1-7) or Ang II at 27 nM concentration produced similar changes in coronary flow, contraction force and heart rate. In isolated hearts perfused with normal Krebs- Ringer, Ang-(1-7) produced a significant enhancement of reperfusion arrhythmias revealed by an increase in the incidence and duration of ventricular tachycardia and ventricular fibrillation (more than 30-min duration). The faciliation of reperfusion arrhythmias by Ang-(1-7) was associated with an increase in the magnitude of the decreased force usually observed during the postischemic period. The effects of Ang-(1-7) were abolished in isolated rat hearts perfused with low-Ca2+ Krebs-Ringer. The effect of Ang II (27 nM) was similar but less pronounced than that of Ang-(1-7) at the same concentration. These results indicate that the heart is a site of action for Ang-(1-7) and suggest that this heptapeptide may be involved in the mediation of the cardiac effects of the RAS.

Utilizaçäo do AMP (2-amino-2-metil-1-propanol) em substituiçäo à DEA (Dietanolamina) na dosagem de fosfato inorgânico no soro e urina pelo método direto de NCL / The use of amp (2-amino-2-methyl-1-propanol) as a substitute of DEA (Diethanolamine) in the determination of inorganic phosphate ins erum and urine, by the MCL direct method

O emprego do AMP (2-amino-2-metil-1-propanol) é proposto como substituto da DEA (Dietanolamina) na determinaçäo de fosfato inorgânico no soro na urina, pelo método direto MCL (Mendes eta al., 1988) Este reagente é mais estável em condiçöes de armazenamento e possui alto poder de solubilizaçäo do precipitado de fosfomolibdato. A análise dos resultados demonstrou uma excelente correlaçäo linear, concluindo que o AMP preenche todos os requisitos necessários para seu emprego na determinacäo de fosfato inorgânico

Perfil hematologico e bioquimico de pacientes com tuberculose / Hematological and biochemical profile of patients carrying lung tuberculosis

Foram colhidas amostras de sangue de 30 pacientes com tuberculose pulmonar comprovada atraves do encontro do B.A.A.R. em esfregaços de escarro corados pelo Ziehl-Neelsen.. As amostras de sangue foram empregadas, atraves de metodologia adequada, para a determinaçao do perfil hematologico e bioquimico dos tuberculosos em busca de alteraçoes que pudessem ser distribuidas a infeccao. Os resultados observados revelaram uma tendencia a leucocitose (23//dos casos com global acima de 10.000/mm3) e um elevado aumento da velocidade de hemossedimentaçao (86//apresentaram elevaçao com media de 72 a 44 mm para mulheres ehomens, respectivamente). A monocitose, referida por varios autores na tuberculose ativa, nao foi observada. Quanto ao perfil bioquimico, os resultados da determinaçao de fosfatase alcalina e valores obtidos de globulinas se mostraram elevados em 46//dos casos. Esses resultados representaram dados preliminares obtidos atraves das avaliaçoes hematologicas e bioquimicas de pacientes com tuberculose,realizadas antes do emprego da terapeutica recomendada. Estes pacientes representam uma amostragem adequadamente selecionada para a primeira etapa do projeto depesquisa sobre a avaliaçao da conduta farmacoterapeutica no setor publico, com aparticipaçao integrada dos Departamentos de Farmacia Social, Produtos Farmaceuticos e Analises Clinicas e Toxicologicas da Faculdade de Farmacia da UFMG.