A Centrally Acting, Anxiolytic Angiotensin II AT(1) Receptor Antagonist Prevents the Isolation Stress-Induced Decrease in Cortical CRF(1) Receptor and Benzodiazepine Binding

21. SAAVEDRA, J M.; ARMANDO, I.; BREGONZIO, C.; JUORIO, A.; MACOVA, M.; PAVEL, J.; SANCHEZ-LEMUS, E

Nature Publishing Group

Año: 2006 vol. 31 p. 1123 - 1123

ong-term pretreatment with an angiotensin II AT1 antagonist blocks angiotensin II effects in brain and peripheral organs and abolishes the sympathoadrenal and hypothalamic-pituitary-adrenal responses to isolation stress. We determined whether AT1 receptors were also important for the stress response of higher regulatory centers. We studied angiotensin II and corticotropin-releasing factor (CRF) receptors and benzodiazepine binding sites in brains of Wistar Hannover rats. Animals were pretreated for 13 days with vehicle or a central and peripheral AT1 antagonist (candesartan, 0.5 mg/kg/day) via osmotic minipumps followed by 24 h of isolation in metabolic cages, or kept grouped throughout the study (grouped controls). In another study, we determined the influence of a similar treatment with candesartan on performance in an elevated plus-maze. AT1 receptor blockade prevented the isolation-induced increase in brain AT1 receptors and decrease in AT2 binding in the locus coeruleus. AT1 rece