ABSTRACT
Objective To investigate the effect of agmatine or agmatine combined with yohimbine on morphine-induced psychological dependence in mice. Methods 1. Testing the effect of agmatine or agmatin combined with yohimbine on basal locomotor activity in 60 minutes. C57BL/6J male mice were divided into four groups:control group, agmatine (1,10,20,40 and 80 mg/kg) groups, yohimbine(0.3,1,2 and 8 mg/kg) groups and yohimbine(2 mg/kg)+ agmatine(80 mg/kg) group. 2. Testing the effects of drug pretreatment on morphine-induced hyperlocomotion in 60 minutes. Mice were divided into five groups: control group, morphine(10 mg/kg) group, agmatine(1,20 and 80 mg/kg)+ morphine(10 mg/kg) group,yohimbine(2 mg/kg)+ morphine(10 mg/kg) group and yohimbine(2 mg/kg)+ agmatine(80 mg/kg)+ morphine(10 mg/kg) group. 3. Observing the effects of agmatine or agmatine combined with yohimbine on morphine induced behavioral sensitization. The mice were administrated with morphine(10 mg/kg) on the 1st , 4th and 7th day and the locomotor activity of mice was recorded for 60 minutes. Mice were divided into four groups: control group, morphine(10 mg/kg) group, agmatine(1,20 and 80 mg/kg) + morphine(10 mg/kg) groups and yohimbine (2 mg/kg)+ agmatine(80 mg/kg)+ morphine(10 mg/kg) group. Results Our present study showed that agmatine(1-80 mg/kg) or yohimbine (0.3-2 mg/kg), a selective antagonist of α2-adrenoceptor, had no significant effect on basal locomotor and acute morphine-induced hyperlocomotion compared with those of control group. However, the distance in the group of agmatine combined with yohimbine followed by morphine for 60 min was(22 581.6±11 694.0) cm,which was significantly lower than the acute morphine group(37 577.9±9 657.4)cm(P<0.05). In the mophine-induced behavioral sensitization model, agmatine(1,20 and 80 mg/kg) alone had no effect on morphine-induced development of behavioral sensitization in mice. But, the combination of the two drugs significantly attenuated morphine-induced behavioral sensitization. The locomotor activities in the combination treatment groups were (21 112.7±5 586.7)cm,(37 672.7±10 518.8)cm and(47 681.0±15 845.3)cm, which were lower than those of morphine group (31 156.4±8 010.5) cm(P<0.01),(51 724.9±11 364.51)cm(P<0.05) and(63 572.2±12 151.2) cm(P<0.05) on the 1st , 4th and 7th day of experiment, respectively. Conclusion Our current results demonstrated that agmatine combined with yohimbine could decrease morphine-induced psychological dependence in mice. It may provide a new strategy for psychological dependence of morphine.
ABSTRACT
Objective To summarize the progresses in laboratory animal science in civil and military fields,and explore the problems existed in development of laboratory animal science in PLA. Methods Literature concerning the laboratory animal science published domestically and abroad were retrospectively and descriptively analyzed. Integrated with the practices on laboratory animal science,the strategies and suggestions for future development of laboratory animal science in PLA were herewith presented. Results Considerable developments have been achieved in the laboratory animal science in PLA,including the improved productive facilities and experimental conditions,and preliminarily established system of traiming of personnal. However,compared with the development level of laboratory animal sciences at home and that of abroad,such disparities as heterogeneity in quality of experimental animals from different breeding institues,lower standard in experimental technology,poorer foundation in the development of animal model special for military purpose,and lack of strategic reserve of laboratory animal resources,etc could still be found. Conclusions The development of laboratory animal science in PLA should depend on a combination of military efforts and civilian support,with establishment of the mechanism to share resources and professional personnel. Meanwhile a long-term mechanism should be developed for professional training of personnel in breeding experimental animals for researches in the field of military medicine,in order to establish a truly fundamental discipline of animal science for research of military medical sciences.