Plasma 5-hydroxyindoleacetic acid as an endogenous index of renal plasma flow

Plasma 5-hydroxyindoleacetic acid as an endogenous index of renal plasma flow. 5-Hydroxyindoleacetic acid (5-HIAA), the major serotonin metabolite, was measured in human plasma and urine using liquid chromatography and electrochemical detection. The renal extraction of 5-HIAA was 78%, a value compatible with an almost complete extraction during a single passage of the blood through the kidney. In addition, plasma levels of 5-HIAA measured in patients with a wide range of renal function was inversely correlated (r = 0.85) with the clearance of para-aminohippuric acid (PAH). The results indicate that 5-HIAA determinations can be used as an alternative procedure to the PAH clearance method for the estimation of renal plasma flow in clinical practice

Impact cardiaque, vasculaire et rénal d'une consommation sodée excessive chez le rat. Traitement pharmacologique des modifications structurales et fonctionnelles

Le but de ce travail est d'étudier l'impact de l'augmentation précoce (sevrage) et de longue durée (5 mois) de l'apport sodé (HS2 ou 8% NaCI), et d'approcher pharmacologiquement les mécanismes. Dans ce modèle on observe le développement d'une hypertrophie cardiaque et vasculaire, et une diminution du taux de filtration glomérulaire, sans fibrose. l'aldostérone et ET1 semblent participer au maintien des altérations dans le régime sévère. Le SRAA tissulaire semble impliqué dans le régime modéré. Le régime sévère est associé à une augmentation du CA2+ dans cellule musculaire lisse, et à l'activité accrue du système NO (augmentation de la sensibilité au NO et au GMPc, activité majorée des BKCa). Ces modifications représenteraient un mécanisme compensateur permettant de maintenir normal le niveau de pression artériellePARIS5-BU-Necker : Fermée (751152101) / SudocPARIS-BIUP (751062107) / SudocSudocFranceF

Tuning of the sequence technique.: Baroreflex in mice

International audienceThe sequence method was first described by Di Rienzo in cats and applied in different species including humans. Until now, no systematic study of spontaneous baroreflex sensitivity (BRS) has been performed by the sequence method in mice. This study aimed to characterize the best estimates of BRS using the sequence method by tuning all the possible parameters, specifically, the number of beats involved in a sequence, the minimal changes in blood-pressure (BP) ramps, and the minimal changes in pulse-interval (PI) ramps. Also, the relevance to set a minimal correlation coefficient in the regression line between BP and PI was tested. An important point was the delay to be applied between BP and PI. This delay represents the physiological time for the baroreflex loop to efficiently correct the BP variations