Neuroadaptive effects induced in the offspring by maternal voluntary ingestion of hypertonic sodium solution: a perinatal imprinting model.

MACCHIONE, AF; VIVAS, L.

Cancun

Congreso; 1er Congreso FALAN (Federación de Asociaciones Latinoamericanas y del Caribe de Neurociencias; 2012

Federación de Asociaciones Latinoamericanas y del Caribe de Neurociencias y Soc. Mexicana de Ciencias Fisiologicas

Neuroadaptive effects induced in the offspring by maternal voluntary ingestion of hypertonic sodium solution: a perinatal imprinting model. Macchione AF, Vivas L. INIMEC-CONICET-UNC, Córdoba, Argentina.   Environmental changes during perinatal period can be programming differentially the systems in the developing offspring, irreversibly and permanently, even into adulthood. Hydroelectrolytic homeostatic systems are not exempt from these effects. The aim of this study was to evaluated the effects of maternal voluntary intake of hypertonic sodium solution on offspring homeostatic mechanisms during adulthood, i.e. neuronal activity along brain groups previously involved in fluid balance regulation, plasma vasopressin (AVP) secretion, AVP-mRNA expression in the supraoptic nucleus (SON) and AT1a-mRNA expression in the subfornical organ (SFO) of adult male rats submitted to a hypertonic sodium infusion (HP). Perinatal manipulation (PM) was carried out in dams from one week before conception until the offspring turned one month old. The experimental groups were: I) PM-Ctrol: free access to water and standard diet, II) PM-Na: free access to the same conditions and voluntary access to a hypertonic sodium solution (0.45M NaCl). When males of the offspring reached adulthood were cannulated and infused with a hypertonic (1.5M NaCl) or isotonic (0.15M NaCl) sodium solution (20 min, 0.15ml/min; iv) or simulated infusion (Sham). Sixty minutes after the end the infusion, brains and plasmas were collected. Our results showed that PM-Na/HP had lower neuronal activity than PM-Ctrol group in the SFO and in the nucleus of the solitary tract. Despite the AVP neuronal activity and plasma AVP secretion showed no differences between groups, the PM-Na/HP group showed a reduced AVP-mRNA expression in the SON, compared to PM-Ctrol/HP. A similar response was observed when the AT1a-mRNA expression was analyzed in the SFO. In sum, our data provide evidence of a neuroadaptative process in animals gestated in rich sodium environment. Support: ANPCyT, CONICET, SECyT.