Assessment of a major depression animal model for old man established with orchidectomized plus olfacto-ry bulbectomized rat / 中华行为医学与脑科学杂志

ABSTRACT

Objective To evaluate the effectiveness of a major depression animal model for old man es?tablished with orchidectomized(ORX) and subsequently olfactory bulbectomized(OBX) rat. Methods Healthy Sprague?Dawley male adult rats were randomly assigned to six groups with ten rats in each groupintact,sham?oper?ated,model,vehicle,fluoxetine plus testosterone propionate(Flu+TP) and amitriptyline plus testosterone propionate (Ami+TP) groups. ORX+OBX rat model was established. Therapy of Flu or Ami (10 mg/kg,i.p.) combined with TP(25 mg/kg,s.c.) was administered. Behavioral changes of rats in each group were detected. Results Open field test The number of rat crossing lattices in model((124.50±14.25)lattices) or vehicle group( 118.70± 10.27) was significantly larger than those of intact(38.20±6.30),sham?operated(33.70±9.58),Flu+TP (34.00± 9.82) and Ami+TP group (35.20±12.54). The rearing number of model or vehicle group was also significantly larger than those of intact,sham?operated,Flu+TP and Ami+TP group.Statistical differences in the above corre?sponding comparisons of open field test existed (P<0.01). Forced swimming test The immobility time of model ((131.70±32.44)s) or vehicle group ((135.10±34.01)s) was significantly longer than those of intact((66.60± 12.06)s),sham?operated((62.00±13.38)s),Flu+TP((59.60±8.89)s) and Ami+TP group ((64.80±10.78)s). There were statistical differences in the above corresponding comparisons (P<0.01). Morris water maze test The escape latency of model((62.00±26.05)s) or vehicle group ((60.52±27.00)s) was significantly longer than those of intact((24.19±9.12)s),sham?operated((21.06±8.13)s),Flu+TP((22.88±8.01)s) and Ami+TP group ((27.04±10.11)s);while the time rat swimming in the quadrant originally put a platform of model or vehicle group was significantly shorter than those of intact,sham?operated,Flu+TP and Ami+TP group. There were statisti?cal differences in the above corresponding comparisons of Morris water maze test (P<0. 01, P<0. 05 ) . Conclusion The above data demonstrates that ORX+OBX rat model is both repeatability and reliability,and can be a major depression animal model of old man for future researches.