INVESTIGADORES
CAEIRO Ximena Elizabeth
artículos
Título:
EFFECT OF SEX CHROMOSOME COMPLEMENT ON SODIUM APPETITE AND FOS IMMUNOREACTIVITY INDUCED BY SODIUM DEPLETION
Autor/es:
DADAM FLORENCIA; CAEIRO XE; CISTERNAS CD; MACCHIONE AF; CAMBIASSO MJ; VIVAS L
Revista:
AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY, INTEGRATIVE AND COMPARATIVE PHYSIOLOGY
Editorial:
AMER PHYSIOLOGICAL SOC
Referencias:
Lugar: Bethesda ; Año: 2014 vol. 1 p. 175 - 184
ISSN:
0363-6119
Resumen:
Dadam FM, Caeiro XE, Cisternas CD, Macchione AF, Cambiasso
MJ, Vivas L. Effect of sex chromosome complement on sodium appetite
and Fos-immunoreactivity induced by sodium depletion. Am J Physiol
Regul Integr Comp Physiol 306: R000?R000, 2014. First published
November 20, 2013; doi:10.1152/ajpregu.00447.2013.?Previous studies
indicate a sex chromosome complement (SCC) effect on the
angiotensin II sexually dimorphic, hypertensive, and bradycardic
baroreflex responses. We sought to evaluate whether SCC may differentially
modulate sexually dimorphic-induced sodium appetite and
specific brain activity due to physiological stimulation of the rennin
angiotensin system. For this purpose, we used the ?four core genotypes?
mouse model, in which the effect of gonadal sex and SCC is
dissociated, allowing comparisons of sexually dimorphic traits between
XX and XY females as well as in XX and XY males.
Gonadectomized mice were sodium depleted by furosemide (50
mg/kg) and low-sodium diet treatment; control groups were administered
the vehicle and maintained on normal sodium diet. Twenty-one
hours later, the mice were divided into two groups: one group was
submitted to the water-NaCl 2% choice intake test, while the other
group was perfused and their brains subjected to the Fos-immunoreactivity
(FOS-ir) procedure. Sodium depletion, regardless of genetic
sex (XX or XY), induced a significantly lower sodium and water
intake in females than in males, confirming the existence in mice of
sexual dimorphism in sodium appetite and the organizational involvement
of gonadal steroids. Moreover, our results demonstrate a SCC
effect on induced brain FOS-ir, showing increased brain activity in
XX-SCC mice at the paraventricular nucleus, nucleus of the solitary
tract, and lateral parabrachial nucleus, as well as an XX-SCC augmented
effect on sodium depletion-induced brain activity at two
circumventricular organs, the subfornical organ and area postrema,
nuclei closely involved in fluid and blood pressure homeostasis.