title: Cognitive enhancing effect of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers on learning and memory.
abstract: OBJECTIVE
  The present study was designed to investigate cognitive enhancing property of angiotensin-converting enzymes inhibitors (ACEI) and angiotensin receptor blockers (ARBs) in rats.
  
  
  METHODS
  The elevated plus maze (EPM), passive avoidance test (PAT), and water maze test (WMT) were used to assess cognitive enhancing activity in young and aged rats. Ramipril (10 mg/kg, p.o.), perindopril (10 mg/kg, i.p), losartan (20 mg/kg, i.p), and valsartan (20 mg/kg, p.o) were administered to assess their effect on learning and memory. Scopolamine (1 mg/kg, i.p) was used to impair cognitive function. Piracetam (200 mg/kg, i.p) was used as reference drug.
  
  
  RESULTS
  All the treatments significantly attenuated amnesia induced by aging and scopolamine. In EPM, aged and scopolamine-treated rats showed an increase in transfer latency (TL) whereas, ACEI and ARBs showed a significant decrease in TL. Treatment with ACEI and ARBs significantly increased step down latencies and decreased latency to reach the platform in target quadrant in young, aged and scopolamine-treated animals in PAT and WMT, respectively. The treatments inhibited acetylcholinesterase (AChE) enzyme in the brain. Similarly, all the treatments attenuated scopolamine-induced lipid peroxidation and normalize antioxidant enzymes.
  
  
  CONCLUSIONS
  The results suggest that the cognitive enhancing effect of ACEI and ARBs may be due to inhibition of AChE or by regulation of antioxidant system or increase in formation of angiotensin IV.
authors.affiliation: Department of Pharmacology, M.V.P. Samaj College of Pharmacy, Gangapur Road, Nashik, Maharashtra, India.
authors.forename: V S
authors.initials: VS
authors.lastname: Nade
authors.affiliation: Department of Pharmacology, M.V.P. Samaj College of Pharmacy, Gangapur Road, Nashik, Maharashtra, India.
authors.forename: L A
authors.initials: LA
authors.lastname: Kawale
authors.affiliation: Department of Pharmacology, M.V.P. Samaj College of Pharmacy, Gangapur Road, Nashik, Maharashtra, India.
authors.forename: K D
authors.initials: KD
authors.lastname: Valte
authors.affiliation: Department of Pharmacology, M.V.P. Samaj College of Pharmacy, Gangapur Road, Nashik, Maharashtra, India.
authors.forename: N V
authors.initials: NV
authors.lastname: Shendye
mesh_terms: D000110:Acetylcholinesterase / Q000187:drug effects; D000375:Aging / Q000523:psychology; D057911:Angiotensin Receptor Antagonists / Q000494:pharmacology*; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology*; D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D001362:Avoidance Learning / Q000187:drug effects*; D001921:Brain / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D018782:Maze Learning / Q000187:drug effects*; D008568:Memory / Q000187:drug effects*; D018697:Nootropic Agents / Q000494:pharmacology*; D010889:Piracetam / Q000494:pharmacology; D051381:Rats; D012601:Scopolamine / Q000037:antagonists & inhibitors / Q000494:pharmacology
chemical_list: D057911:Angiotensin Receptor Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D000975:Antioxidants; D018697:Nootropic Agents; D012601:Scopolamine; D000110:Acetylcholinesterase; D010889:Piracetam
keywords: Acetylcholinesterase; angiotensin IV; lipid peroxidation; scopolamine