ABSTRACT
Objective To develop a multi-mode,detailed and sensitive object recognition method for learning and memory research,including novel object recognition task,object location recognition task,temporal order memory task and object context recognition task in animals based on their spontaneous behavior. Methods Two strains of mice(KM and ICR)and four patterns were used to establish the object recognition method and several relative factors,such as time of test phase,delay between test phase and familiar phase were investigated. Results It was stable and reasonable to set the time of familiar phase as 5 min,the interval between test phase and familiar phase as 10 min,and the time of test phase as 3-5 min,under the precondition of habituation for three days and selecting the appropriate object pairs. Conclusions Object recognition test including four patterns has been systematically established as a stable, reliable and normative way for the research of animal learning and memory and drug development.
ABSTRACT
Objective To investigate the effects of chronic restraint stress on learning and memory in Wistar and Sprague-Dawley (SD) rats.Methods Healthy adult male Wistar rats (n=6) and Sprague-Dawley rats (n=6) were subjected to restraint stress 10 h daily for 28 days.After that, all rats were tested for recognition memory by novel object recognition test , and spatial memory and working memory by Morris water maze test .Results After restraint for 10 h daily for 28 days, the restraint rats of the two strains demonstrated lower discrimination index (DI)than the control group, but on-ly SD rats showed significant difference ( P<0.05 ) .The restraint SD rats showed higher escape latency than the control rats, and on the 5th day the difference became significant (P<0.05), and there was no significant difference between Wistar restraint and control rats .The working memory test showed that restraint SD rats exibited longer escape latency than the control rats (P<0.05), while Wistar rats didn’t show significant difference between the two groups .Conclusions The results of this study demonstrate that the impairments of learning and memory in SD rats subjected to restraint 10 hour per day for 28 days are more serious than that in the Wistar rats .Therefore , SD rats may be a better choice as an animal model to study the effects of chronic restraint stress on learning and memory impairment .
ABSTRACT
Objective To evaluate the technical feasibility and clinical efficacy of retroperitoneal and transperitoneal laparoscopic nephrectomy for nonfunctional kidney with giant hydronephrosis. Methods The clinical data of retroperitoneal group (26 patients) and transperitoneal group (23 patients) who underwent laparoscopic nephrectomy for nonfunctional kidney with giant hydronephrosis were analyzed retrospectively. Compared with operating time,kidney size, blood loss, postoperative intestinal function recovery time, postoperative hospital stay and operative efficacy of the two groups. Results All the operations were performed successfully. Operating time,kidney size and blood loss were not significantly different between two groups(P＞ 0.05). While in retroperitoneal group, postoperative intestinal function recovery time and postoperative hospital stay were significantly reduced than those in transperitoneal group [( 18.0 ± 1.2)h vs. (48.0 ±2.0) h, (5.5± 1.6) d vs. (7.5 ± 1.6) d](P＜0.05). All patients were followed up 1 -3months,no abnormal. Conclusions The retroperitoneal and transperitoneal laparoscopic nephrectomy for nonfunctional kidney with giant hydronephrosis can be performed efficiently and effectively. Retroperitoneal laparoscopic is better than transperitoneal laparoscopic on postoperative recovery aspects.