en Cellular & Molecular Research Cellular & Molecular Research Original Research Original Research <p> <strong> Background: </strong>It is well known that the hippocampus, the CA1 Pyramidal cells in particular, is selectively vulnerable during global cerebral ischemia. Recently, it is observed that pentoxifylline has a neuroprotective effect. This study explored the pharmacological relationship between ischemia-induced cell death of the hippocampus and the efficacy of a vasodilator agent (pentoxifylline) in the prevention of delayed neuronal death. </p><p> <strong> Methods </strong>: This experimental study was performed on 4 groups: control, ischemia, experimental (200mg/kg pentoxifylline injection one hour prior to and one hour following ischemia) and vehicle (normal saline). Transient global ischemia was induced by bilateral common carotid arteries occlusion. To investigate the apoptotic bodies and caspase-3 activities as a central role in the execution phase of apoptosis, the brains were prepared for the TUNEL technique. </p><p> <strong> Results </strong>: Pentoxifylline administration limited apoptosis and caspase-3 activities in rats’ hippocampi. Our data showed no significant difference between the number of apoptotic bodies in the CA1 region of the hippocampus in the control and pentoxifylline -treated groups (p= 0.994). The results of one- way ANOVA revealed that that ischemia significantly increased caspase-3 levels in the hippocampus (p<0.05) however, the level of caspase-3 in pentoxifylline -treated rats was less than the ischemic group. </p><p> <strong> Conclusion </strong>: These results suggest that the neuroprotective effect of pentoxifylline (200mg/kg) may be accompanied by a reduction in ischemic damage within the CA1 region of the hippocampus in rats subjected to transient global cerebral ischemia. </p> Cerebral ischemia, Reperfusion, Pentoxifylline, Hippocampus. 279 287 http://mjiri.iums.ac.ir/browse.php?a_code=A-10-1-835&slc_lang=en&sid=1 Zahra Nadia Sharifi nadiasharifi@yahoo.com 200319475328460016459 200319475328460016459 No Department of Anatomy, Islamic Azad University, Tehran Medical Branch, Tehran, Iran. Shabnam Movassaghi sm_movassaghi@yahoo.com 200319475328460016460 200319475328460016460 No Department of Anatomy, Islamic Azad University, Tehran Medical Branch, Tehran, Iran. Farzaneh Mohamadzadeh farzaneh.mohammadzadeh@yahoo.com 200319475328460016461 200319475328460016461 No Departmentof Anatomy, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran. Sara Soleimani Asl S.soleimaniasl@umsha.ac.ir 200319475328460016462 200319475328460016462 No Department of Anatomy, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran. Bagher Pourheydar bagher.pourheydar@gmail.com 200319475328460016463 200319475328460016463 No Neurophysiology Research Center, Department of Anatomy, Urmia University of Medical Sciences, Urmia, Iran. Mehdi Mehdizadeh mehdizadeh.m@iums.ac.ir 200319475328460016464 200319475328460016464 Yes Cellular and Molecular Research Center, Faculty of Advanced Technologies in Medicine, Department of Anatomy, Iran University of Medical Sciences, Tehran, Iran