Background and Aim Drug-induced sensitization in the mesocorticolimbic systems has been thought to play an important role in certain aspects of drug addiction, including the important function of drug-associated cues ...Background and Aim Drug-induced sensitization in the mesocorticolimbic systems has been thought to play an important role in certain aspects of drug addiction, including the important function of drug-associated cues and environments in mediating drug-seeking behaviors. Our previous studies have identified a role of heat shock protein 70 （Hsp70） in the development of a single exposure morphine-induced behavioral sensitization. Methods The present study investigated the effect of environment on the expression of behavioral sensitization in- duced by a single morphine exposure, and associated Hsp70 levels. Results Our results showed that expression of single exposure morphine-induced behavioral sensitization was accompanied by a significant increase of Hsp70 ex- mice administered morphine in an unpaired fashion failed pression in the nucleus accumbens （NAc）. In contrast, to exhibit behavioral sensitization or higher Hsp70 expression. Additionally, by using a habituation process before we found that there was a transition from conditioned hyperactivity to be- challenge to remove conditioned response, havioral sensitization, the former of which was not accompanied by an increased expression of Hsp70. Conclusions Together, these results suggest that behavioral sensitization induced by a single morphine exposure in mice exhib- its context- and time-dependent patterns with environmental context functioning probably via an inhibitory condition- ing mechanism. Alteration of Hsp70 expression in NAc may represent a neurobiological sensitization mechanism mediating context- and time-dependent behavioral sensitization.展开更多
The expanded ammonium nitrate (EAN) samples with different states were prepared by using a vacuum crystallizing technology. The structure characters,such as porosity,pore structure,specific surface area,particle surfa...The expanded ammonium nitrate (EAN) samples with different states were prepared by using a vacuum crystallizing technology. The structure characters,such as porosity,pore structure,specific surface area,particle surface shape and surface defects,and detonator initiation sensitivity and explosion power,of common ammonium nitrate (AN) and EAN were tested using density measuring,N2 adsorbing,scanning electron microscope (SEM) and plate trace test methods. The tested results show that the particle surface of common AN is smoother,denser,lower porosity and specific surface area than those tested of EAN. The particle surface of EAN is irregular,which has edges,protuberance and severely distorted crystal form,and its specific surface area and porosity are larger than those of un-expanded AN. EAN has typical self-sensitization structure characters. The detonator initiation sensitivity and explosion power of ammonium nitrate-fuel oil(ANFO) made of different states of EAN are related to the self-sensitization structures of EAN,and expanded ANFO sample has higher detonator initiation sensitivity and explosion power compared with un-expanded ANFO sample. The characterization techniques can be used to reveal the self-sensitization structure of EAN.展开更多
文摘Background and Aim Drug-induced sensitization in the mesocorticolimbic systems has been thought to play an important role in certain aspects of drug addiction, including the important function of drug-associated cues and environments in mediating drug-seeking behaviors. Our previous studies have identified a role of heat shock protein 70 （Hsp70） in the development of a single exposure morphine-induced behavioral sensitization. Methods The present study investigated the effect of environment on the expression of behavioral sensitization in- duced by a single morphine exposure, and associated Hsp70 levels. Results Our results showed that expression of single exposure morphine-induced behavioral sensitization was accompanied by a significant increase of Hsp70 ex- mice administered morphine in an unpaired fashion failed pression in the nucleus accumbens （NAc）. In contrast, to exhibit behavioral sensitization or higher Hsp70 expression. Additionally, by using a habituation process before we found that there was a transition from conditioned hyperactivity to be- challenge to remove conditioned response, havioral sensitization, the former of which was not accompanied by an increased expression of Hsp70. Conclusions Together, these results suggest that behavioral sensitization induced by a single morphine exposure in mice exhib- its context- and time-dependent patterns with environmental context functioning probably via an inhibitory condition- ing mechanism. Alteration of Hsp70 expression in NAc may represent a neurobiological sensitization mechanism mediating context- and time-dependent behavioral sensitization.
文摘The expanded ammonium nitrate (EAN) samples with different states were prepared by using a vacuum crystallizing technology. The structure characters,such as porosity,pore structure,specific surface area,particle surface shape and surface defects,and detonator initiation sensitivity and explosion power,of common ammonium nitrate (AN) and EAN were tested using density measuring,N2 adsorbing,scanning electron microscope (SEM) and plate trace test methods. The tested results show that the particle surface of common AN is smoother,denser,lower porosity and specific surface area than those tested of EAN. The particle surface of EAN is irregular,which has edges,protuberance and severely distorted crystal form,and its specific surface area and porosity are larger than those of un-expanded AN. EAN has typical self-sensitization structure characters. The detonator initiation sensitivity and explosion power of ammonium nitrate-fuel oil(ANFO) made of different states of EAN are related to the self-sensitization structures of EAN,and expanded ANFO sample has higher detonator initiation sensitivity and explosion power compared with un-expanded ANFO sample. The characterization techniques can be used to reveal the self-sensitization structure of EAN.
