Tese de Doutorado
Perfil circulante dos componentes do sistema reninaangiotensinaem gestantes normais e portadoras de Diabetes tipo 1 e Diabetes gestacional
Fecha
2005-07-13Autor
Anelise Impeliziere Nogueira
Institución
Resumen
physiopathogeny of diabetes mellitus complications. During pregnancy RAS is physiologically activated but little is known about it in gestations associated with gestational diabetes or preexistent type I diabetes. Pregnancy can worse the cronical complications related to diabetes. Preeclampsia, an hypertensive disease of pregnancy also linked to RAS changes, is more frequent in diabetic patients. Gestational diabetes is considered a model for the study of type II diabetes sinc these women show high risc of becoming diabetic later in life and, as demonstratedby some authors, endothelial dysfunctions are present after labor even with normal glycemic levels. The objective of this study was to evaluate the circulating profile of RAS in non-hypertensive pregnancies in women with type I diabetes or gestat diabetes, with good glycemic control and absence of cronical complications and compare them to non-pregnant and pregnant women with and without diabetes. The patients were distributed in six groups: 1) non-pregnant and non-diabetics; 2)pregnant and non-diabetics; 3) non-pregnant with type I diabetes; 4) pregnant with type I diabetes; 5) patients with gestational diabetes controlled with diet and 6 patients with gestational diabetes controlled with insulin. Frequent consultations were realized in endocrinological and obstetrical ambulatories where selection of patients was accomplished. The RAS evaluation was made by plasma measurement of ANG I, ANG II, ANG-(1-7) and Plasmatic Renin Activity (PRA). Among the non-pregnant women, the type I diabetic shown elevated of ANG I and PRA levels when compared to the non-diabetic (p<0,05). In pregnancy, there were higher levels of angiotensins and PRA when compared to non-diabetic women, non-pregnant and pregnant, suggesting physiological activation os RAS. In pregnancies of type I diabetics the activation of ANG I and ANG-(1-7) was even higher, showing hyperactivation of these RAS components. In this group, however, there was RAS activation, as occurred in normal pregnants, in exception of lack of elevation of ANG-(1-7) levels (p<0,05). This observation was confirmed by the significativelly lower ANG-(1-7) /ANG I relation (p<0,05). RAS is physiologically activated during pregnancy, with equilibrium among the angiotensins but, in pregnant type I diabetics, the higher elevation of ANG-(1-7) can be linked to endothelial and/or glomerular protection. In pregnants with gestational diabetes, there was significative elevationof ANG I, discrete elevation of ANG II and significative reduction of ANG-(1-7) This last finding can be related to the persistence of endothelial dysfunction observed in this women, including after labor, when glycemic levels return to normal. This even be the link between gestational diabetes, preeclampsia and later cardiovasculardysfunction.