INIMEC - CONICET   05467
INSTITUTO DE INVESTIGACION MEDICA MERCEDES Y MARTIN FERREYRA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
TRPV1 OSMOSENSITIVE CHANNEL INVOLVEMENT IN THE CONTROL OF SODIUM APPETITE
Autor/es:
CAEIRO XE.; ANTUNES-RODRIGUES J.; QUIRÓS COGNUCK, S; REIS. L; PORCARI CY; GODINO A; MECAWI, A; VIVAS L.
Lugar:
BUENOS AIRES
Reunión:
Congreso; REUNIÓN CONJUNTA DE SOCIEDADES DE BIOCIENCIAS 2017; 2017
Institución organizadora:
Sociedades Argentinas de Investigacón en Biociencias
Resumen:
There is a temporal dissociation between sodium depletion (SD) and the appearance of sodium appetite (SA) behavior. After an acute SD, the natremia decreases immediately however SA takes at least 16 h to appear. Our recent results demonstrated in Wistar rats that the transient receptor potential vanilloid type 1 (TRPV1) channel, required for normal osmoregulation, is involved in SA control. The TRPV1 mRNA expression was increased in the kidney and previously involved brain nuclei, during the delay of SA (2 h after SD) and significantly decreased during the appearance of SA (24 h after SD), possibly allowing the hypertonic sodium consumption. The aim of the present work was to evaluate in TRPV1 knockout mice (KO), sodium intake and the urinary pattern of renal excretion at different times after SD. In particular, we analyzed the sodium and water intake and the renal response at 2 h and 24 h after SD induced by furosemide (50mg/kg) in combination with low sodium diet in wild type (WT) and KO mice.After SD, the KO animals showed an increase in the sodium preference (F=8.49; p=0.006) and consumed a higher hypertonic cocktail (F=8.49; p=0.0059) in relation to WT animals, independent of the time after SD. These data suggest that KO animals, when stimulated to drink water and sodium, make a hypertonic cocktail instead of the isotonic one usually made by the control animals. The urinary volume (F=5.45; p=0.0003) and sodium excretion (F=3.99; p=0.028) induced by Furosemide at 30 minutes were both reduced in KO animals in comparison to WT. There was no change in plasma osmolality between the groups 2 h and 24 h after SD. In sum, these data suggest that the TRPV1 channels are involved in the osmoregulatory behavioral and renal responses after acute body SD.Keywords: sodium depletion, sodium appetite, TRPV1, osmoregulation.Support: CNPq; CONICET; Foncyt, Secyt