Participation of the brain angiotensinergic system in the neonatal Hypoxia-Ischemia Lesion.

LÓPEZ AGUILERA F.; ALVAREZ D.; BONAFEDE M.; MENEO G.; SELTZER A.M.

Mendoza, Argentina

Congreso; XXVI Reunión Científica Anual de la Sociedad de Biología de Cuyo I Reunión de la Dirección de Investigación, Ciencia y Técnica del Ministerio de Salud Gobierno de Mendoza; 2008

Sociedad de Biología de Cuyo

Participation of the brain angiotensinergic system in the neonatal Hypoxia-Ischemia Lesion.  López-Aguilera F (*),  Alvarez D (§), Bonafede M (ß),  Meneo G (ƒ) y Seltzer A (*). (*) IHEM-CONICET, (§) UNSL, (ß IMBECU-CONICET), (ƒ)UJAM. Email:aseltzer@fcm.uncu.edu.ar Previous data indicate that in the adult brain the AT2 receptors of Angiotensin II (ATII) exert neuroprotective actions. AT1 blockers  decrease the infarcted areas, and this may be related to an increase of AT2 receptors activity. ATII regulates cerebrovascular flow and blood vessel´s compliance through AT2 receptors.  We attempt to further explore the participation of ATII in the hypoxic-ischemic (H-I) lesion in the immature brain Seven-day old pups of Wistar Kyoto rats where preconditioned (PCon). On the next day, the right common carotid artery was ligated and cut under light anesthesia Control animals where sham operated. and submitted to asphyxia (N2 100%,2-4m) Controls breathed room air.  Animals were sacrificed at 24,48h and 7-30 days after H-I.  RT-PCR: We observed that the mRNA of the AT2 receptor remained constant in all groups at 24 h post lesion (n=9 animals; 3 groups of 3 animals each). Western Blot:  At 24h post lesion, the AT2 protein  increased in both hemispheres, showing a larger increase at the ipsilateral side.  By 48h the values tend to normalize. PCon animals showed attenuated effects. Immunohistochemistry: In fixed and cryoprotected slices of the lesioned animals we explore the expression of the AT2 receptor together with gliosis, apoptosis and vascularization.