[Hypertension: retrospective study in children from a pediatric nephrology unit]. / Hipertensão arterial: estudo retrospectivo em crianças referendadas a uma unidade de nefrologia pediátrica.

300 hypertensive children, from newborn to 18 years old,were studied, retrospectively, from 1975 to 1992, 105 from those lost for follow-up. In 244 the diagnosis of the primary disease, predominantly glomerulopathy, was established. 122 had chronic renal failure (CRF). From them, 74 arrived at end stage renal disease (ESRD) and 13 have been transplanted. From 12 submitted to surgical treatment, hypertension has been controlled in 8. 54 died, 48 with CRF and 38 with ESRD. Difficulties in controlling those patients are discussed, mainly therapy diet, the use of hypotensive drugs on dialysis treatment. Our conclusion is for the necessity of a precocious diagnosis for hypertension and primary diseases, of a trained interprofessional team as well as availability of adequate equipment to children, mainly for dialytic therapy. For many of these children, renal transplantation is the only definite therapy.

Differential baroreceptor reflex modulation by centrally infused angiotensin peptides.

The present study was designed to investigate the effect of intracerebroventricular (icv) and intravenous (iv) infusion of angiotensin (ANG)-(1-7), ANG III, and ANG II on the baroreceptor control of heart rate (BHR) in conscious rats. Reflex changes in HR were elicited by bolus iv injection of either phenylephrine or sodium nitroprusside before and within 1 and 3 h of icv infusion of ANG II (n = 10), ANG III (n = 9), ANG-(1-7) (n = 9), or saline (n = 9) at a rate of 3 nmol.7.5 microliter-1.h-1. In another group of animals (n = 23), iv infusion of the same amount of ANG peptides was carried out at a rate of 0.7 ml/h. The average ratio of changes in HR in beats per minute and changes in mean arterial pressure (MAP, mmHg) was used as an index of BHR sensitivity. ANG II and ANG III produced a significant increase in the basal levels of MAP, but only during the first hour of infusion (iv or icv). No significant changes in baseline HR were observed. ANG-(1-7) and saline infusion did not change basal levels of HR or MAP (iv or icv). ANG II (iv and icv) and ANG III (icv) caused a significant decrease in the BHR sensitivity for reflex bradycardia. In contrast, icv infusion of ANG-(1-7) induced a significant increase in BHR sensitivity for reflex bradycardia (-3.0 +/- 0.3, 1 h, and -2.8 +/- 0.1 beats.min-1.mmHg-1, 3 h vs. -2.1 +/- 0.2 beats.min-1.mmHg-1, before infusion).(ABSTRACT TRUNCATED AT 250 WORDS)