en Clinical Neuroscience Clinical Neuroscience Original Original <p align="left" ><font color="#221e1f" size="2"><font color="#221e1f" size="2"><p align="left" ><p><strong><font color="#221e1f" size="2"><font color="#221e1f" size="2">Introduction: </font></font><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2">Alzheimer’s disease (AD) is a enfeeble neurodegenerative disorder characterized by increased </font></font></font><font color="#221e1f" face="Calibri,Calibri" size="2"><font color="#221e1f" face="Calibri,Calibri" size="2"><font color="#221e1f" face="Calibri,Calibri" size="2">β</font></font></font><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2">-amyloid (A</font></font></font><font color="#221e1f" face="Calibri,Calibri" size="2"><font color="#221e1f" face="Calibri,Calibri" size="2"><font color="#221e1f" face="Calibri,Calibri" size="2">β</font></font></font><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2">) deposition and neuronal dysfunction leading to impaired learning and recall. Among proposed risk factors, impaired cholinergic transmission is a main cause for incidence of disease. </font></font></font></strong><font color="#221e1f" size="2"><font color="#221e1f" size="2"><p align="justify"><strong>Methods: </strong></p></font></font><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2">In the present study, effects of the intracerebroventricularly administration of an agonist of nicotinic cholinergic receptors, varenicline(0.5 and 2 μg/μl), on learning and memory impairments induced by intrahippocampal A</font></font></font><font color="#221e1f" face="Calibri,Calibri" size="2"><font color="#221e1f" face="Calibri,Calibri" size="2"><font color="#221e1f" face="Calibri,Calibri" size="2">β</font></font></font><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2">(25–35) injection was assessed in rats. </font></font></font><font color="#221e1f" size="2"><font color="#221e1f" size="2"><p align="justify"><strong>Results: </strong></p></font></font><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2">The results showed that the intrahippocampal A</font></font></font><font color="#221e1f" face="Calibri,Calibri" size="2"><font color="#221e1f" face="Calibri,Calibri" size="2"><font color="#221e1f" face="Calibri,Calibri" size="2">β</font></font></font><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2">(25–35) injected rats exhibit lower spontaneous alternation score inY-maze tasks (p<0.05), impaired retention and recall capability in the passive avoidance test (p<0.05), and fewer correct choices (p<0.001) and more errors(p<0.001) in the RAM task. Varenicline, </font></font></font><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2">almost in both doses, significantly improved alternation score in Y-maze task </font></font></font><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2">(p<0.001), impaired retention and recall capability in the passive avoidance test (p<0.05), and correct choices in the RAM task (p<0.001). </font></font></font><font color="#221e1f" size="2"><font color="#221e1f" size="2"><p><strong>Discussion: </strong></p></font></font><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2">This study indicates that varenicline pretreatment attenuates A</font></font></font><font color="#221e1f" face="Calibri,Calibri" size="2"><font color="#221e1f" face="Calibri,Calibri" size="2"><font color="#221e1f" face="Calibri,Calibri" size="2">β</font></font></font><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2"><font color="#221e1f" face="Times New Roman,Times New Roman" size="2">- induced impairment of short-term spatial memory in rats probably due to its agonist activity at nicotinic receptors. </font></font></font></p></font></font> Aβ(25–35),Varenicline,Passive Avoidance,Y Maze,Radial Maze,Rat 48 57 http://bcn.iums.ac.ir/browse.php?a_code=A-10-1-92&slc_lang=en&sid=1 Tourandokht Baluchnejadmojarad 1370031947532846001430 1370031947532846001430 Yes Mehrdad Roghani 1370031947532846001431 1370031947532846001431 No Narges karimi 1370031947532846001432 1370031947532846001432 No Mitra kamran 1370031947532846001433 1370031947532846001433 No