Availability of a rich source in sodium chloride during perinatal period modifies the fluid balance restoration pattern in adult offspring.

MACCHIONE AF; VIVAS L

Simposio; 1st Brazilian International Symposium on Integrative Neuroendocrinology; 2011

International Neuroendocrine Federation

There are many studies supporting fetal origins hypothesis, which postulates that pregnancy or perinatal history program differentially the developing offspring, affecting them even in adulthood. Hydroelectrolyte system can be altered for electrolyte or endocrine environmental changes during perinatal period causing consequences in the water or sodium intake pattern. The aim of this study was to examine the effect of the availability of a rich source in sodium during perinatal period on the fluid balance restoration pattern. We studied sodium and water intake and brain pattern of Fos (Fos-ir) and Fos-vasopressin (Fos-AVP-ir) immunoreactivity in adult offspring after sodium depletion. Perinatal manipulation (PM) was carried out in dams from one week before conception until the end of lactation. The experimental groups were: I) PM-No Exposed (PM-No Exp): free access to tap water and standard diet, II) PM-Exposed (PM-Exp): free access to tap water, standard diet and were exposed to a hypertonic sodium solution (0.45M NaCl) of voluntary access. For behavioral studies, adult offspring were sodium depleted by sc Furosemide (40mg/kg) and sodium-free diet, which induces hypovolemic thirst. Moreover, for brain immunoreactivity pattern analysis we used two doses of furosemide (8 and 40mg/kg). In sodium depleted rats, cumulative volumes of sodium and water intake were significantly minor in PM-Exp vs. PM-No Exp. These data would indicate that PM-Exp’s animals can be differentially sensing the osmotic load of ingested solutions. Regarding brain analysis, we observed a large number of activated cells (like Fos-ir and Fos-AVP-ir) in subfornical organ and supraoptic nucleus of the PM-Exp vs. PM-No Exp. Thus, PM-Exp animals consumed lower volumes of both solutions during the test and had higher levels of neuronal activation. These results indicate the existence of differences in how PM-Exp animals reestablish their hydromineral balance, suggesting they have a larger anticipatory response may be because of central osmosensitive mechanism alterations. Our data demonstrate a long-term effect of maternal hypertonic sodium solution exposure, altering mechanisms that regulate fluid balance in the offspring. Financial Support: ANPCyT, CONICET and SECyT.