The Onset Of Sodium Appetite: Role Of Oxitocinergic And Serotonergic Central Systems.

PORCARI CY; CAEIRO XE.; MECAWI, A; REIS. L; ANTUNES-RODRIGUES J.; VIVAS L.; GODINO A

CORDOBA

Congreso; XXXIII Congreso Anual de la Sociedad Argentina de Investigación en Neurociencias; 2018

Sociedad Argentina de Investigación en Neurociencias

A temporal dissociation exists between sodium depletion(SD) and the appearance of sodium appetite(SA) 20h later; thus, an inhibitory modulation was postulated. Our previous studies demonstrated an inhibitory involvement of serotonergic(5-HT) and oxytocinergic(OT) neurons on SA regulation. Our aim was to evaluate gene expression changes of different components of central OT and 5HT systems, during the delay of SA appearance after SD. Wistar rats were SD using furosemide combined with low sodium diet, and 2h or 24h later the rats were decapitated. Specific brain areas: dorsal raphe nucleus(DRN), subfornical organ(SFO), lateral parabrachial(LPBN) and anteroventral area of third ventricle plus supraoptic nucleus(AV3V+SON), were submitted to RT-PCR of oxytocin receptor(OTR), serotonin 2A receptor(5HT2A), tryptophan hydroxylase 2(TPH2) and serotonin transporter(SERT). OTR mRNA expression significantly increased(p=0.045) early at 2h after SD in the AV3V+SON in comparison to control and 24h-SD groups. In the DRN the OTR mRNA expression followed the same tendency increasing 2h after SD and decreasing 24h later, in comparison to control and 2h SD groups, however these differences did not reach significant levels(p=0.06).Non-significant changes in the SERT and TPH2 mRNA expression were found in the DRN and the 5HT2A mRNA expression in the LPBN and SFO. In sum, our results suggest that OT circuits acting in nuclei previously involved in SA regulation may modulate SA appearance.