Brain changes of serotonergic 5HT2C receptor and oxytocin expression after an acute body sodium depletion

PORCARI, CINTIA; MACAGNO, AGUSTINA; VIVAS, LAURA; GODINO, ANDREA

Carlos Paz

Congreso; XXXIV Reunión Anual SAN 2019; 2019

Sociedad Argentina de Investigación en Neurociencias

A temporal dissociation exists between sodium depletion(SD) and the appearance of sodium appetite(SA); and an inhibitory modulation of oxytocinergic and serotonergic(5HT) systems has been postulated. Our recent results also demonstrated a specific temporal pattern of serotonergic and oxytocin receptor mRNA expression,(5HT2C and OTR, respectively), along different brain areas after SD. Our aim was to evaluate 5HT2C and OT proteins expression, during the delay of SA appearance after SD. Wistar rats were SD using furosemide combined with a low sodium diet, and 2h or 24h later were decapitated.Protein samples were extracted of dorsal raphe nucleus(DRN), subfornical organ(SFO), lateral parabrachial(LPBN), araventricular nucleus(PVN) and supraoptic nucleus(SON), and then were analyzed by western blot.The OT+NP expression increased(p=0.001) after SD in the PVN in Comparison to control groups(CD). The 5HT2C expression significantly increased (p=0.0088) and decreased (p=0.0018) after SD along DRN and LPBN respectively, in comparison to CD.The 5HT2C expression in the SFO and the OT+NP expression in the SON did not change.However, none of these proteins within the different nuclei showed a temporal effect. Our results indicate that SD differentially change the expression of 5HT2C and OT-NP along PVN, DRN and LPBN suggesting that they are modulated by sodium status, allowing excitatory and inhibitory CNS signals integration in order to reach the water and sodium balance.