生理性进食之后静息态fMRI脑功能连接的变化

The alterations of resting-state brain functional connectivity after physiological food intake

目的探讨生理性进食之后静息态脑功能连接的变化。材料与方法 42名健康被试按照人口统计学特征平衡分为三组。为了增加胃肠活动的差异,三组分别服用多潘立酮、奥替溴铵、安慰剂。所有被试均给予标准实验早餐,于空腹、早餐后、餐后2h及午餐前行静息态功能磁共振(functional MRI,fMRI)检查。数据分析采用扣带回后部-楔前叶作为种子点,计算全脑功能连接,并采用重复测量ANOVA分析在时间与药物因素上具有显著差异的脑区,并提取其功能连接Z值,进行事后检验。结果时间主效应:右侧眶额回/壳核/丘脑、右侧缘上回和右侧岛盖的功能连接在时间因素上有显著差异(P<0.05)。药物主效应:右侧楔前叶、左侧颞中回、左侧舌回、右侧颞中回、右侧额上回、双侧眶额回、左侧额中回的功能连接在药物因素上有显著差异(P<0.05)。结论静息态fMRI健康被试生理性进食前后,奖赏系统、右侧丘脑和躯体感觉区的功能连接会发生变化,并且呈现右侧偏侧化优势;胃动力药物对上述脑区的变化无影响。为常规fMRI实验中被试进食状态对实验结果的潜在影响提供了分析依据。

Objective:To explore the alterations of resting state brain functional connectivity after physiological food intake.Materials and Methods:Forty-two healthy subjects were divided into three groups in a balanced order according to the demographic characteristics.To maximize the differences of gastrointestinal activity of the three groups,three medicines were given to the three groups,including Domperidone(promote group),Otilonium Bromide(inhibition group),and dummy(control group).All the participants were given standard experiment diet for breakfast.And the resting state fMRI scanning was performed at 4 different gastrointestinal physiological states,specifically fasting,postprandial immediately,2 h postprandial and before lunch.During data analysis,the posterior cingulate/precuneus(PCC/PCu)were selected as the seed to calculate the functional connectivity(FC)throughout the whole brain.Then the repeated measure analysis of variance(ANOVA)was used to investigate the brain areas with significant differences across the time and medicine.The brain regions with significant differences were further extracted the Z functional connectivity value which were subsequently involved into the post hoc analysis.Results:The main effect of time:significant FC changes across time were found in the right orbitofrontal cortex/putamen/thalamus,right supramarginal gyrus,and right Rolandic lobe(P<0.05).The main effect of medicine:significant FC changes across medicine were found in the right precuneus,left middle temporal gyrus,left lingual gyrus,right middle temporal gyrus,right superior frontal gyrus,bilateral orbitofrontal cortex and left middle frontal gyrus(P<0.05).Conclusions:The FC of the food reward system,the right thalamus and somatosensory regions demonstrated changes after physiological food intake,showing right lateralization.While no significant differences were found in these areas across medicine.This study may provide possible implications for analyzing the potential effects of food intake on the results of conventional fMRI experiments.