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Comorbidity exists between hypertension and depression and anxiety in humans. Therefore, open field (OF) and forced swim test (FST) were used to evaluate anxiety- and depressive-like properties in hypertension. Anxiogenic behavior was proportional to time spent in the periphery of the OF (thigmotaxis). A Depressive-like state was proportional to time spent immobile during the FST. Unilaterally nephrectomized Sprague Dawley rats were subjected to renal wrap or 14 day aldosterone (aldo; 0.75 µg/hr) treatment. Aldo rats were hypertensive (135±6mmHg vs 104±5 mm Hg), however no behavioral differences were observed. Interestingly, wrap rats were hypertensive 7 (146±7mmHg vs 115±3mmHg) and 28 (159±6mmHg vs 108±3mmHg) days post surgery and spent more time in the periphery of OF compared to sham at 7 (223±15 vs 178±8 s) and 28 days (231±10 vs 199±15 s). No significant differences were observed in the FST. The centrally-administered MR antagonist RU28318 (100ng) had no effect on blood pressure in either model of hypertension, however it significantly decreased immobility in the FST of both aldo- and saline-treated rats and reduced thigmotaxic behaviors in all rats. These data demonstrate that renal wrap hypertension generates anxiety-like behavior in the rat. Although central MRs may not be involved in aldo-induced or renal wrap hypertension, blockade of MRs produce an anxiolytic effect and mimic antidepressant actions in these models. [ABSTRACT FROM AUTHOR]