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Objective To examine white matter integrity in heroin-dependent patients and matched normal controls with diffusion tensor imaging (DTI).Methods The fractional anisotropy was compared between 15 heroin-dependent patients and 15 controls.Results We found the fractional anisotropy was significantly decreased in specific brain regions of the heroin-dependent patients (P ＜ 0.001 uncorrected),including the frontal gyrus,the parietal lobule,the insula,and the corpus callosum.Conclusion The presence of microstructural abnormality is found in the white matter of several brain regions of heroin-dependent patients.
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Objective To explore what brain regions are modulated by heroin addiction and withdrawal.MethodsWe used functional magnetic resonance imaging to investigate the brain function in 15 heroin-dependent patients 3 days (acute) and 1 month (protracted) after heroin abstinence.Sixteen normal controls were included.Results The blood oxygen level-dependent signal in the orbitofrontal cortex of the brain of heroin-dependent patients was significantly elevated 3 days after the withdrawal.Hyperfunction of the orbitofrontal cortex declined 1 month after the withdrawal.Conclusion Heroin-dependent subjects at both 3 days and 1 month abstinence have persistent abnormalities in the brain function.Although some tangible beneficial effects are noted following 1month of detoxification,possible permanent damage to the brain caused by heroin use is suggested.
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ObjectiveTo investigate the effects of nicotine exposure and ethanol-preferring behavior on mRNA expression of some nAChR subunits in the rat ventral tegmental area(VTA) and to explore possible mechanisms of dependence on tobacco and alcohol.Methods39 male Wistar rats,35-day-old,were randomly divided into an experimental group (group N,n=20) and a control group (group C,n=19).Rats in group N were treated with nicotine ( 1.0 mg · kg -1 · d -1 ) by subcutaneous injection while in group C with saline both for 10 days,after which 6 rats (respectively group NE,n =6,group CE,n =6 )were drawn randomly from each group and killed by cutting off the head.mRNA was extracted from the VTA tissue,and the expression of nAChR subunits,including α4,α5,α7 and β2,were examined by Real Time-PCR.Other rats both in groups N and C ( respectively group NA,n=14,group CA,n=13) were induced for 69 days to establish two-bottle free choice alcohol-preferring behavior model by Samson sucrose fading program from 60-day-old on.The same indexes mentioned above were detected by the same methods in the VTA tissue.Results① The factor analysis showed that both the two factors,nicotine and alcohol-preferring behavior,showed regulating effects on the expression of nAChR subunits α4 and α5 ( respectively F was 6.13,5.407,5.186,7.132,P ＜ 0.05 ),and the factor,alcohol-preferring behavior,on subunit β2 (F =5.896,P＜0.05) ; the two factors exhibited strong interaction on the expression of subunit α7 (F=13.894,P＜0.001 ),and some interaction on subunits α5 and β2 (respectively F was 6.149,4.222,P＜0.05 ).② The mRNA expression of nAChR subunits α4,α5,α7,and β2 were significantly up-regulated by different degrees in group NA compared to group CA ( respectively Fwas 7.941,13.517,17.438,9.272,respectively P ＜ 0.05,P ＜ 0.05,P ＜ 0.01,P ＜ 0.01 ),the expression level of subunits α4,α5,α7 and β2 were significantly higher in different degrees in group NA than in group NE( respectively F was 5.293,8.500,6.149,4.837,P ＜0.05) ; while subunit α7 was significantly down-regulated in group CA compared to group CE (F =12.750,P ＜0.01 ).ConclusionNicotine and ethanol co-affect on the nAChR subtype comprised of subunits α4,α5,α7 and β2.
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OBJECTIVE@#To explore the regional homogeneity of resting state brain activity in early onset schizophrenia using functional magnetic resonance imaging.@*METHODS@#Schizophrenia or schizophreniform disorder was diagnosed according to DSM-IV-TR (diagnostic and statistical manual of mental disorders, fourth edition, text revision). A total of 18 adolescents with early-onset schizophrenia (EOS; onset of psychotic symptoms by age 18) and 18 age- and gender-matched healthy volunteers were tested in a resting-state fMRI scan. Regional homogeneity approach was used to analyze the functional imaging data,and statistical parametric mapping 5 (SPM5)was used to perform t-test in ReHo maps between the patients and controls.@*RESULTS@#In comparison with the controls, the early-onset patients showed significantly decreased regional homogeneity in bilateral medial prefrontal cortex(P20), but no brain regions showed significantly increased regional homogeneity in the patients.@*CONCLUSION@#Regional homogeneity of resting state brain activities in EOS was decreased in bilateral medial prefrontal cortex. These abnormal changes may be involved in the psychopathology of schizophrenia.