Effects of chronic 5-bromo-2-deoxyuridine administration on spatial memory in the adult rats

5-Bromo-2-deoxyuridine [BrdU] has been a principal marker for mitotic cells in studies of adult neurogenesis. The method consists of a pulse injection of BrdU into the intraperitoneal cavity followed by a variable survival time allowing for tracking the divided cells and their progeny. However, such exogenous markers may produce toxic effects. Aim of this study was determined the effects of Brdu on spatial memory in the adult rat. 16 Wistar rats were used in this experimental study. The rats were randomly divided into 2 groups [N=8 in each group], as follows: control and Brdu [50 mg/kg]. Brdu was administered intraperitoneally for 6 weeks and then animals were used for behavioral testing in the Morris water maze. The data were analyzed with repeated measure's ANOVA. Our present findings show that there were no differences in the path length, escape latency and swim speed between control and Brdu-administrated groups. This study show that Brdu [exogenic proliferation marker] did not has side effects on spatial memory in the adult rats

Chronic treatment by L-nAME differently affects morris water maze tasks in ovariectomized and naive female rats

Introduction: The role of ovarian hormones and nitric oxide [NO] in learning and memory and their interaction has been widely investigated. The present study carried out to evaluate different effect of L-NAME on spatial learning and memory of ovariectomized [OVX] and sham operated rats. Methods: 32 rats were divided into 4 groups: 1] Sham; 2] OVX; 3] Sham-LN; and 4] OVX-LN. The animals of groups 3 and 4 were treated by L-NAME [10 mg/kg/ day] for 8 weeks while the animals of groups 1 and 2 received saline [1ml/kg/day] instead of L-NAME. The animals of all groups were then tested in Morris water maze during five days. The escape latency and traveled distance were compared between groups. Results: Distance and time in OVX group was significantly higher than Sham group [p<0.01 and p<0.05]. Time and distance in Sham-LN group was higher in comparison with Sham group [p<0.05 and p<0.01]. There were no significant differences between OVX-LN and OVX groups in escape latency and traveled distance. Discussion: The results of present study showed that removal of ovarian hormones could impair Morris water maze tskas includiong time and distance. Administarion of non specific nitricoxide inhibitor, L-NAME, affects Morrsi water maze tasks however, its effect is different in the absence and presence of ovarian hormones but it needs to be more investigated