ramipril and Memory-Disorders

This study was designed to evaluate the spatial working memory (as studied in Y-maze) or short-term and long-term spatial memory (assessed in radial 8 arms-maze task), in a scopolamine-induced memory deficits model in mice, by the oral administration of 2 angiotensin-converting enzyme inhibitors-captopril and ramipril and also the effects of the AT1 receptor antagonist, losartan. The present article was initiated as a reaction to the clinical setting of hypertensive disease, which involves lifelong administration of antihypertensive drugs, dietary or lifestyle constraints, and aging, which all take a toll on the higher functions of the nervous system. Most of the patients with cognitive decline suffer of various metabolic imbalances, hypertension, cardiac and kidney disease, many of them which are treated with oral administration of Renin-angiotensin aldosterone system-altering agents like those presented above. Our results showed a protective effect of captopril, ramipril, and losartan prescopolamine administration on spontaneous alternation in Y-maze task, as compared to scopolamine-alone treated mice, as well as decreased number of working memory errors and reference memory errors in radial-arm maze for both losartan + scopolamine and ramipril + scopolamine groups versus scopolamine alone. This could have a therapeutical relevance, especially since oral administration was preferred in our report, as it is used in the therapeutic procedures in humans, further enhancing the similarities with the clinical conditions.

Topics: Administration, Oral; Angiotensin II Type 1 Receptor Blockers; Angiotensin-Converting Enzyme Inhibitors; Animals; Captopril; Humans; Losartan; Male; Maze Learning; Memory Disorders; Memory, Long-Term; Memory, Short-Term; Mice; Muscarinic Antagonists; Ramipril; Renin-Angiotensin System; Scopolamine; Spatial Memory

Treatment with erythropoietin and AT1 blockers is protective in experimental acute cerebral ischemia, with promising results in pilot clinical studies in human stroke. This paper examines the effects of using both agents as combination therapy in acute ischemic stroke.. We used the single carotid ligation stroke model in the gerbil. Six groups of 50 gerbils were treated either with placebo, erythropoietin (intraperitoneally, 5000 IU/kg, 2 and 48 h after stroke), olmesartan (10 mg/kg per day in drinking water started 36 h after stroke), ramipril (2.5 mg/kg per day in drinking water started 36 h after stroke), erythropoietin + olmesartan, or erythropoietin + ramipril. Long-term (1 month) Kaplan-Meyer survival curves were obtained, and survivors were submitted at day 30 to immediate (object recognition test) and spatial (Morris water maze) memory function tests.. Erythropoietin alone and olmesartan alone, but not ramipril, significantly increased survival at day 30 compared with untreated controls (38, 30 and 6% versus 12%, respectively). Combined treatment with erythropoietin and olmesartan further increased the survival rate to 56%, whereas combined therapy with erythropoietin and ramipril decreased 30-day survival to 24% (P < 0.0001, erythropoietin + olmesartan versus erythropoietin + ramipril). Untreated stroke survivors had markedly altered performances in both the object recognition test (P = 0.0007) and the Morris water maze (P < 0.0001) tests at day 30 compared with normal gerbils. In erythropoietin-treated animals, ramipril therapy had no beneficial effect whereas olmesartan fully restored normal response to the memory tests.. Post-infarct treatment with olmesartan combined with early erythropoietin therapy has a protective effect on survival, and markedly improves long-term memory dysfunction in this experimental model.

Topics: Angiotensin II Type 1 Receptor Blockers; Angiotensin-Converting Enzyme Inhibitors; Animals; Disease Models, Animal; Drug Therapy, Combination; Erythropoietin; Gerbillinae; Imidazoles; Kaplan-Meier Estimate; Male; Memory Disorders; Neuroprotective Agents; Ramipril; Recombinant Proteins; Stroke; Tetrazoles