BACKGROUND: Drug addiction involves two main central nervous systems, namely the dopamine and noradrenaline systems. These systems are primarily distributed in five brain regions: the ventral tegmental area, the nuc...BACKGROUND: Drug addiction involves two main central nervous systems, namely the dopamine and noradrenaline systems. These systems are primarily distributed in five brain regions: the ventral tegmental area, the nucleus accumbens, the prefrontal cortex, the hippocampus, and the locus coeruleus. OBJECTIVE: To investigate regional changes of guanine nucleotide binding protein-inhabitant 2 (Gi2) in dopaminergic and noradrenergic neurons in brains of morphine-tolerant and -dependent rats. DESIGN, TIME, AND SETTING: A randomized control study was performed at the Department of Neurobiology in the Second Military Medical University of Chinese PLA (Shanghai, China) between September 2002 and March 2004. MATERIALS: Thirty-six, healthy, male, Sprague-Dawley (SD) rats were used to establish morphine-dependent models. Morphine hydrochloride was a product of Shenyang First Pharmaceutical Factory (China); naloxone hydrochloride was a product of Beijing Four-Ring Pharmaceutical Factory (China); and α subunit of Gi2 antibody was offered by Santa Cruz Biotechnology, lnc (USA). METHODS: Thirty-six SD rats were randomly divided into six groups (n = 6): (1) acute morphine-dependent group, (2) acute abstinent group, (3) acute control group, (4) chronic morphine-dependent group, (5) chronic abstinent group, and (6) chronic control group. Rats in the acute morphine-dependent and the acute groups were injected with morphine (5 mg/kg), one injection every two hours, for a total of eight injections. In the acute and chronic morphine-dependent rat models, morphine withdrawal syndrome was precipitated by an injection of naloxone (5 mg/kg). Rats in the acute control group were given a peritoneal injection of physiological saline at the same administration time as the above two groups. Rats in the chronic morphine-dependent and chronic abstinent groups were injected with morphine three times per day. The administration dose on day 1 was initially 5 mg/kg at 20:00, w展开更多
文摘BACKGROUND: Drug addiction involves two main central nervous systems, namely the dopamine and noradrenaline systems. These systems are primarily distributed in five brain regions: the ventral tegmental area, the nucleus accumbens, the prefrontal cortex, the hippocampus, and the locus coeruleus. OBJECTIVE: To investigate regional changes of guanine nucleotide binding protein-inhabitant 2 (Gi2) in dopaminergic and noradrenergic neurons in brains of morphine-tolerant and -dependent rats. DESIGN, TIME, AND SETTING: A randomized control study was performed at the Department of Neurobiology in the Second Military Medical University of Chinese PLA (Shanghai, China) between September 2002 and March 2004. MATERIALS: Thirty-six, healthy, male, Sprague-Dawley (SD) rats were used to establish morphine-dependent models. Morphine hydrochloride was a product of Shenyang First Pharmaceutical Factory (China); naloxone hydrochloride was a product of Beijing Four-Ring Pharmaceutical Factory (China); and α subunit of Gi2 antibody was offered by Santa Cruz Biotechnology, lnc (USA). METHODS: Thirty-six SD rats were randomly divided into six groups (n = 6): (1) acute morphine-dependent group, (2) acute abstinent group, (3) acute control group, (4) chronic morphine-dependent group, (5) chronic abstinent group, and (6) chronic control group. Rats in the acute morphine-dependent and the acute groups were injected with morphine (5 mg/kg), one injection every two hours, for a total of eight injections. In the acute and chronic morphine-dependent rat models, morphine withdrawal syndrome was precipitated by an injection of naloxone (5 mg/kg). Rats in the acute control group were given a peritoneal injection of physiological saline at the same administration time as the above two groups. Rats in the chronic morphine-dependent and chronic abstinent groups were injected with morphine three times per day. The administration dose on day 1 was initially 5 mg/kg at 20:00, w