Effects of Ovariectomy and 17<i>β</i>-Estradiol Replacement on Dopamine D2 Receptors in Female Rats: Consequences on Sucrose, Alcohol, Water Intakes and Body Weight

Background: Mechanisms underlying overeating-induced obesity in post-menopausal woman include functional lack of 17β-estradiol dysregulating dopamine D2 receptors, thereby inducing food addiction, glucose craving or alcohol dependence through reward circuitry. This study aimed at further understanding 17β-estradiol and dopamine D2 receptors interferences in the etiology of woman obesity. Method: Seventy-two Wistar female rats weighing 200 - 205 g, individually-housed, were divided into non-ovariectomized control (C = 6 groups) and ovariectomized rats (OVX = 6 groups) which were concurrently subjected to the following treatments: Non-drug-treated (DMSO vehicle), 17β-estradiol (E2, 5 μg/kg, s.c.), sulpiride (SUL, 20 mg/kg, i.p.), bromocriptine (BR, 0.1 mg/kg, i.p.), E2 + SUL or E2 + BR, designating the 6 constitutive groups of either control or ovariectomy. Within each experimental group, consumption of different solutions (10% alcohol, 10% sucrose and water) as well as food intake and body weight were daily measured, for 10 consecutive days. Results: This study indicated that D2S was a specific inducer of alcohol and food intakes, but reduced sugar consumption. In addition, 17β- estradiol regulated the body weight set point, modulating D2S functions towards increased food intake at lower weights and decreased food intake at higher weights. D2S met the slow genomic actions induced by 17β-estradiol. Conversely, D2L inhibited alcohol and food intakes, but induced specifically sugar consumption, thereby regulating blood glucose levels and promoting energy expenditure in reducing body weight. Indeed, 17β-estradiol exerted a tonic inhibition on D2L which was released by OVX, exacerbating sugar intake and increasing body weight. D2L mediated the rapid metabolic effects of 17β-estradiol. Conclusion: Our results supported physiological data reporting that activation of the mostly expressed presynaptically D2S-class autoreceptors decreased dopamine release stimulating food intake, whereas activation of the predominantly postsynaptic isoform D2L receptors increased dopamine activity inhibiting food intake. Our studies indicated that 17β-estradiol acted on the two types of D2 receptors showing opposite functions to equilibrate energy intake vs. expenditure for weight set point regulation. Our data also supported biochemical findings reporting that 17β-estradiol induced D2 genes transcriptional regulation, thereby involving both types of D2 receptors in the etiology of obesity. The combined dysregulated effects of D2L and D2S receptors, as 17β-estradiol was lacking, would be causal factors underlying the etiology of obesity.

Down-regulation of dopamine D2 receptor associates with impaired reversal learning induced by morphine withdrawal

OBJECTIVE Cognitive inflexibility plays a critical role in the compulsive drug taking,a central characteristic of drug addictions,yet its underlying neurochemical mechanisms are not well understood.The present study examined the impact of morphine withdrawal on reversal learning.METHODS Reversal learning was tested in a four-choices digging task.Some brain tissues were harvested 2 h after the behavioral experiment for the further measurement.RESULTS We found that after long-term abstinence for a month from chronic morphine exposure,mice exhibited a profound reversal learning deficit.We further found that dopamine D2 receptor(D2R)system in the frontal-striatal circuit is significantly down-regulated,at both receptor and downstream signals levels.Subsequent pharmacological experiments demonstrated that aripiprazole,a D2R partial agonist,prevented the D2R downregulation and rescued the reversal learning deficit.CONCLUSION Together,our findings provide valuable insights into the causal relationship between D2R system in the frontal-striatal circuit and the cognitive inflexibility caused by abused drugs and offer a promising possibility of an effective therapeutic intervention for drug addictions.

Modeling of Dopamine D2 Receptor and its Agonist DOCK Analyses

A model of transmembrane helices of dopamine D2 receptor was constructed using the X ray coordinates of bacteriorhodopsin (BR) as a template. Based on the results from the model and the site directed mutagenesis experience, the binding pocket, including nine amino acid residues beside indispensable Asp86, Ser141 and Ser144 residues, was defined. In order to testify the 3D structure of dopamine D2 receptor and specially test the binding sites, two sets of D2 receptor agonists (one was rigid and the other flexible) were selected for docking. A good result of correlation between logIC 50 and binding energy E b indicates that the predicted model is reliable for the investigation of the receptor ligand interaction and design of new active molecules.

Effects of septal nucleus lesion on dopamine D_2 receptor expression in the prefrontal lobe, striatum, and brainstem in a rat model of schizophrenia

BACKGROUND： It has been demonstrated that the septal nucleus is involved in the pathogenesis of schizophrenia. Based on autopsies of schizophrenia patients, studies have shown a reduced number of septal nucleus neurons and glia. In addition, experimental rat models of schizophrenia have shown increased dopamine receptor D2 binding sites in the basal ganglia, septal nuclei, and substantia nigra. Previous studies have demonstrated that the septal nucleus modulates dopamine metabolic disorder and dopamine D2 receptor balance. OBJECTIVE： Dopamine D2 receptor expression in a rat model of schizophrenia, combined with antipsychotic drugs, was analyzed in the prefrontal lobe, striatum, and brainstem. In situ hybridization was used to observe the effects of stereotactic septal nucleus lesions on dopamine D2 receptor expression in the brains of methylamphetamine-treated rats. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment was performed in the Laboratory of General Institute of Psychosurgery, Third Hospital of Chinese PLA from November 2005 to June 2006. MATERIALS： A total of 120 healthy, adult Sprague Dawley rats, weighing approximately 200 g, were included. Methylamphetamine （Sigma, USA） and an in situ hybridization detection kit for dopamine D2 receptor （Boster, China） were also used for this study. METHODS： All rats were randomly allocated to the following 4 groups, with 30 rats in each group： normal control, simple administration, septal nucleus lesion, and sham-operated groups. In the normal control group, rats were not administered or lesioned. In the remaining 3 groups, rats were intraperitoneally administered 10 mg/kg methylamphetamine, once per day, for 15 successive days to establish a schizophrenia model. Following successful model establishment, rats from the septal nucleus lesion group were subjected to stereotactic septal nucleus lesions. The cranial bone was exposed in rats from the sham-operated group, and the septal nucleus was not lesioned. MAIN OUTCOME MEASURES： At 7 days post-surgery, dopamine D2 receptor expression in the prefrontal lobe, striatum, and brainstem were detected by in situ hybridization. RESULTS： Dopamine D2 receptor expression in the rat prefrontal lobe, striatum, and brainstem was significantly higher in the simple administration group and sham-operated group, compared with the normal control group （P 〈 0.01）. In the septal nucleus lesion group, dopamine D2 receptor expression was significantly less than the simple administration and sham-operated groups, （P 〈 0.01）. There was no significant difference in dopamine D2 receptor expression between the simple administration and sham-operated groups （P 〉 0.05）. CONCLUSION： Septal nucleus lesions reduce dopamine D2 receptor expression in the prefrontal lobe, striatum, and brainstem in a rat model of schizophrenia, indicating that the septal nucleus modulates dopamine D2 receptor expression.

Effect of total isoflavones from pueraria lobata on the expressions of preproenkephalin, prodynorphin and D2 dopamine receptor mRNA in PC12 cells induced by MPP^+

Objective： The aim of the study was to observe the effect of total isoflavones from pueraria Iobata （TIP） on D2 dopamine receptor mRNA, preproenkephalin mRNA and prodynorphin mRNA expressions in Parkinson＇s disease （PD） model cells induced by 1-methyl-4-phenylpyridinium ion （MPP^＋）. Methods： TIP was dissolved in 0.1 M NaOH and added to the culture medium at a final concentrations of 50 mg/L, 100 mg/L and 200 mg/L. Some cells （control） were exposed to 0.001 M NaOH. TIP was added to PC12 cells 30 min prior to the administration of MPP^＋. TIP and MPP^＋ remained in the culture medium for 96 h. D2 dopamine receptor mRNA, preproenkephalin mRNA and prodynorphin mRNA expressions were assayed by real-time quantitative reverse transcription-PCR. Results： The D2 dopamine receptor mRNA and preproenkephalin mRNA expressions were up-regulated in MPP^＋ group compared with the control group, and prodynorphin mRNA expression was down-regulated in that. The D2 dopamine receptor mRNA expression being down-regulated and prodynorphin mRNA expression being up-regulated in TIP group compared with the MPP^＋ group. And there was no effect of TIP on preproenkephalin gene expression in PC12 cells induced by MPP^＋. Conclusion： The results suggest that TIP down-regulates the D2 dopamine receptor mRNA expression, up-regulates prodynorphin mRNA expression and not affects preproenkephalin gene expression in PC12 cells induced by MPP^＋.

SOX2/DRD2 signaling pathway facilitates astrocytic dedifferentiation in cerebral ischemic mice

Objective:To explore the effects of dopamine receptor D2(DRD2)on astrocytic dedifferentiation based on SOX2-regulated genes in neural stem cells(NSCs)and astrocytes.Methods:Immunofluorescence staining and SOX2-GFP mice were used to examine the lineage differentiation of SOX2-positive cells during the development of cerebral cortex.Primary NSCs/astrocytes culture,ChIP-seq and Western Blot were adopted to analyze and verify the expression of candidate genes.Pharmacological manipulation,neurosphere formation,photochemical ischemia,immunofluorescence staining and behavior tests were adopted to evaluate the effects of activating DRD2 signaling on astrocytic dedifferentiation.Results:Immunofluorescence staining demonstrated the NSC-astrocyte switch of SOX2-expression in the normal development of cerebral cortex.ChIP-seq revealed enrichment of DRD2 signaling by SOX2-bound enhancers in NSCs and SOX2-bound promoters in astrocytes.Western Blot and immunofluorescence staining verified the expression of DRD2 in NSCs and reactive astrocytes.Application of quinagolide hydrocholoride(QH),an agonist of DRD2,significantly promoted astrocytic dedifferentiation both in vitro and in vivo following ischemia.In addition,quinagolide hydrocholoride treatment improved locomotion recovery.Conclusion:Activating DRD2 signaling facilitates astrocytic dedifferentiation and may be used to treat ischemic stroke.

Effects of endogenous dopamine induced by low concentration atropine eye drops on choroidal neovascularization in high myopia mice

AIM:To evaluate effects of endogenous dopamine induced by low concentration atropine eye drops on choroidal neovascularization(CNV)in high myopia mice.METHODS:The C57BL/6J mice were deprived of the right eye for 4wk,and the high myopia was diagnosed by optometry,the diopter was less than-6.00 D,and CNV was induced by 532 nm laser.The changes of dopamine D1 receptor(DRD1),dopamine D2 receptor(DRD2),and vascular endothelial growth factor A(VEGFA)were detected by Western blot technology at 0.5,1,2h,and 7d after 0.01%,0.05%,and 0.1%atropine eye drops,respectively,the area of CNV was measured.RESULTS:Significant increases were observed on the expression of DRD2 in mouse high myopia model at 0.5,1,2h,7d with 0.05%and 0.1%atropine eye drops(P<0.05).Significant decreases were observed on the expression of DRD1 and VEGFA in mouse high myopia model at 0.5,1,2h,7d with 0.05%and 0.1%atropine eye drops(P<0.05).The area of CNV induced by laser in the drug-treated group was significantly smaller than that in the control group,and the higher the concentration,the more significant the inhibitory effect(P<0.05).CONCLUSION:The 0.01%,0.05%,0.1%atropine eye drops can decrease the level of VEGFA and inhibit high myopia CNV indirectly by up-regulating the level of DRD2 and down-regulating the level of DRD1,and the effect of 0.05%and 0.1%atropine eye drops is more significant.

The hypothalamic-spinal dopaminergic system:a target for pain modulation

Nociceptive signals conveyed to the dorsal horn of the spinal cord by primary nociceptors are subject to extensive modulation by local neurons and by supraspinal descending pathways to the spinal cord before being relayed to higher brain centers. Descending modulatory pathways to the spinal cord comprise,among others, noradrenergic, serotonergic, γ-aminobutyric acid(GABA)ergic, and dopaminergic fibers.The contributions of noradrenaline, serotonin, and GABA to pain modulation have been extensively investigated. In contrast, the contributions of dopamine to pain modulation remain poorly understood.The focus of this review is to summarize the current knowledge of the contributions of dopamine to pain modulation. Hypothalamic A11 dopaminergic neurons project to all levels of the spinal cord and provide the main source of spinal dopamine. Dopamine receptors are expressed in primary nociceptors as well as in spinal neurons located in different laminae in the dorsal horn of the spinal cord, suggesting that dopamine can modulate pain signals by acting at both presynaptic and postsynaptic targets. Here, I will review the literature on the effects of dopamine and dopamine receptor agonists/antagonists on the excitability of primary nociceptors, the effects of dopamine on the synaptic transmission between primary nociceptors and dorsal horn neurons, and the effects of dopamine on pain in rodents. Published data support both anti-nociceptive effects of dopamine mediated by D2-like receptors and pro-nociceptive effects mediated by D1-like receptors.

多巴胺D_2受体基因启动子A-241G多态性在精神分裂症家系中的连锁不平衡传递

目的 :探讨多巴胺D2 受体基因 (dopamineD2 receptor,DRD2 )启动子A 2 41G多态性与精神分裂症的关系。方法 :采集 10 1个家系 ,每家有 2名或 2名以上符合ICD 10精神分裂症诊断标准患病同胞且父母存活。对DRD2启动子的A 2 41G多态性进行检测。结果 :(1)DRD2启动子的A 2 41G等位基因频度和基因型频度在父母组、非患病同胞组和患病同胞组之间差异无显著性 ,在 3组不同性别之间以及在精神分裂症不同亚型之间基因型频度和等位基因频度的分布差异亦无显著性 ;(2 )传递不平衡检验发现在患病同胞 (χ2 =0 .94,P >0 .0 5 ,OR =0 .83,95 %可信区间 0 .5 7～ 1.2 1)中未表现传递不平衡性 ,而在非患病同胞 (χ2 =6 .76 ,P <0 .0 1,OR =3 .17,95 %可信区间 0 .41～ 2 4.71)中存在传递不平衡性 ,其中 2 41A等位基因在非患病同胞中传递较多 ;(3)基因型与妄想总分、幻觉总分、思维形式障碍、情感障碍、精神性失语及症状持续时间等临床特征相关。结论 :DRD2启动子的A 2

多巴胺D_2受体启动子区域基因多态性与抽动-秽语综合征的关联分析

目的 :探讨抽动 秽语综合征 (TS)与多巴胺D2 受体启动子区域 (DRD2P)多态性的关系 .方法 :应用聚合酶链反应 限制性片断长度多态性技术对 2 4例患儿和 30例正常对照进行DRD2P基因 1 4 1CDel/Ins多态性和TS的关联性分析 .结果 :共检出 2种基因型 :纯合子 1 4 1CIns/Ins(1 6 0bp ,1 4 4bp)与杂合子 1 4 1CDel/Ins(30 4bp ,1 6 0bp ,1 4 4bp) ,未检出纯合子 1 4 1CDel/Del(30 4bp ,30 4bp) .病例组 1 4 1CDel/Ins多态性的基因型频率与对照组的差异无显著性 (χ2 =0 .0 93,ν=2 ,P >0 .0 5 ) ;等位基因频率比较也无显著性差异 (χ2 =0 .0 6 0 ,ν=1 ,P >0 .0 5 ) .结论 :抽动 秽语综合征与DRD2P基因 1 4

多巴胺D_2受体显像剂^(125)I-IBZM的合成与标记

合成了标记前体Ｓ－（－）－２－羟基－６－甲氧基－Ｎ－［（１－乙基－２－吡咯烷基）甲基］苯甲酰胺（Ｓ－（－）－ＢＺＭ）。光谱数据与结构相符。以Ｓ－（－）－ＢＺＭ为前体，用１２５Ｉ－ＮａＩ标记，成功地制备了Ｓ－（－）－３－１２５Ｉ－２－羟基－６－甲氧基－Ｎ－［（１－乙基－２－吡咯烷基）甲基］苯甲酰胺（Ｓ－１２５Ｉ－ＩＢＺＭ）。标记率大于８０％，放射化学纯度大于９０％，整个制备过程仅需４５ｍｉｎ，利于药盒化生产。

^(131)I-IBZM脑多巴胺D_2受体SPECT显像在帕金森病的临床应用价值

目的 探讨131I-IBZM脑多巴胺D2 受体SPECT显像在帕金森病中的临床应用价值。方法 对 12例帕金森病 (PD)和 4例正常对照者进行131I-IBZM脑多巴胺D2 受体SPECT显像。结果 131I -IBZM高度特异性地在双侧基底节浓聚。正常对照两侧无差别。 6例早期PD两侧积聚不对称 ,起病肢体对侧基底节放射性积聚明显高于对侧相应部位。病侧肢体对侧的BG/OC和BG/FC比值较同侧高 (P <0 .0 1) ;长期服用多巴制剂的 6例中晚期PD两侧积聚、BG/OC和BG/FC比值无明显差别 ,但均低于正常对照组 (P <0 .0 1)。结论 131I -IBZMSPECT显像可评价脑多巴胺D2 受体的功能状态 。

苯并[d]噁唑啉-2-酮-5-羧酸的合成研究

利用较价廉的3-硝基-4-羟基苯甲酸在Pd/C催化下氢化还原得3-氨基-4-羟基苯甲酸,再与氯甲酸甲酯(或氯甲酸乙酯)成环得苯并[d]噁唑啉-2-酮-5-羧酸。目标化合物经1H NMR和MS确证,总收率为81.6%。该方法工艺简单,条件温和,收率较高,便于工业合成。

Estrogen affects neuropathic pain through upregulating N-methyl-D-aspartate acid receptor 1 expression in the dorsal root ganglion of rats

Estrogen affects the generation and transmission of neuropathic pain,but the specific regulatory mechanism is still unclear.Activation of the N-methyl-D-aspartate acid receptor 1（NMDAR1） plays an important role in the production and maintenance of hyperalgesia and allodynia.The present study was conducted to determine whether a relationship exists between estrogen and NMDAR1 in peripheral nerve pain.A chronic sciatic nerve constriction injury model of chronic neuropathic pain was established in rats.These rats were then subcutaneously injected with 17β-estradiol,the NMDAR1 antagonist D（-）-2-amino-5-phosphonopentanoic acid（AP-5）,or both once daily for 15 days.Compared with injured drug na？ve rats,rats with chronic sciatic nerve injury that were administered estradiol showed a lower paw withdrawal mechanical threshold and a shorter paw withdrawal thermal latency,indicating increased sensitivity to mechanical and thermal pain.Estrogen administration was also associated with increased expression of NMDAR1 immunoreactivity（as assessed by immunohistochemistry） and protein（as determined by western blot assay） in spinal dorsal root ganglia.This 17β-estradiol-induced increase in NMDAR1 expression was blocked by co-administration with AP-5,whereas AP-5 alone did not affect NMDAR1 expression.These results suggest that 17β-estradiol administration significantly reduced mechanical and thermal pain thresholds in rats with chronic constriction of the sciatic nerve,and that the mechanism for this increased sensitivity may be related to the upregulation of NMDAR1 expression in dorsal root ganglia.

Neuroprotective effects of tadalafil on gerbil dopaminergic neurons following cerebral ischemia

Impairment of dopamine function, which is known to have major effects on behaviors and cognition, is one of the main problems associated with cerebral ischemia. Tadalafil, a long-acting phosphodiesterase type-5 inhibitor, is known to ameliorate neurologic impairment induced by brain injury, but not in dopaminergic regions. We investigated the neuroprotective effects of treatment with tadalafil on cyclic guanosine monophosphate level and dopamine function following cerebral ischemia. Forty adult Mongolian gerbils were randomly and evenly divided into five groups （n = 8 in each group）： Sham-operation group, cerebral ischemia-induced and 0, 0.1, 1, and 10 mg/kg tadalafil-treated groups, respectively. Tadalafil dissolved in distilled water was administered orally for 7 consecutive days, starting 1 day after surgery. Cyclic guanosine monophosphate assay and immunohistochemistry were performed for thyrosine hydroxylase expression and western blot analysis for dopamine D2 receptor expression. A decrease in cyclic guanosine monophosphate level following cerebral ischemia was found with an increase in thyrosine hydroxylase activity and a decrease in dopamine D2 receptor expression in the striatum and substantia nigra region. However, treatment with tadalafil increased cyclic guanosine monophosphate expression, suppressed thyrosine hydroxylase expression and increased dopamine 92 receptor expression in the striatum and substantia nigra region in a dose-dependent manner. Tadalafil might ameliorate cerebral ischemia-induced dopaminergic neuron injury. Therefore, tadalafil has the potential as a new neuroprotective treatment strategy for cerebral ischemic injury.

Renaldopaminergic system:Pathophysiological implications andclinical perspectives

Fluid homeostasis, blood pressure and redox balance in the kidney are regulated by an intricate interaction between local and systemic anti-natriuretic and natriuretic systems. Intrarenal dopamine plays a central role on this interactive network. By activating specifc receptors, dopamine promotes sodium excretion and stimulates anti-oxidant and anti-inflammatory pathways. Different pathological scenarios where renal sodium excretion is dysregulated, as in nephrotic syndrome, hypertension and renal infammation, can be associated with impaired action of renal dopamine including alteration in biosynthesis, dopamine receptor expression and signal transduction. Given its properties on the regulation of renal blood fow and sodium excretion, exogenous dopamine has been postulated as a potential therapeutic strategy to preventrenal failure in critically ill patients. The aim of this review is to update and discuss on the most recent findings about renal dopaminergic system and its role in several diseases involving the kidneys and the potential use of dopamine as a nephroprotective agent.

(-)-Stepholodine induced enhancement of cardiac muscle contractions mediated by D_1 receptors

Objective To investigate the effect of(-)-Stepholidine(SPD)on enhancing D1 receptor mediated contraction of cardiac muscle in isolated rat heart and to examine whether SPD has a direct effect on the heart dopamine D1 receptors.SPD an active ingredient of the Chinese herb Stephania intermedia,binds to dopamine D1 and D2 like receptors.Biochemical,electrophysiological and behavioural experiments have provided strong evidence that SPD is both a D(1/5)agonist and a D(2/4)antagonist,which could indicate unique antipsychotic properties.Methods Normal adult rat working hearts were isolated by Langendorff technique.Results SPD significantly increased the cardiac muscle contraction in a dose-dependent manner.The selective D1 dopamine receptor antagonist SCH23390(1 μM)blocked the SPD induced heart contraction,however,neither the β-receptor antagonist propranolol(1 μM)nor the α1-receptor antagonist prazosin(1 μM)had any effect on blocking SPD induced heart contractions.Moreover,the L-type Ca2+ channel inhibitor nimodipine(1 μM)completely blocked the effect of SPD on cardiac muscle contraction.Conclusions SPD show the effect on enhancing contraction of isolated rat heart through activating L-type Ca2+ channel mediated by heart D1 receptors.

多巴胺D_2受体TaqIA多态性与海洛因依赖行为相关性

目的 :探讨多巴胺 (DA)受体D2 亚型基因TaqIA多态性与海洛因依赖者行为之间的相关性。方法 :应用PCR -RFLP法对 6 6例海洛因依赖病人与 132例正常人D2 R基因的TaqIA多态性特征进行对照研究。以A型行为问卷 (TABPQ) [1] 测评海洛因依赖者的行为类型 ,与其TaqIA多态性特征进行相关分析。结果 :海洛因依赖组与正常对照组DRD2 基因的TaqIA多态性基因型及等位基因频率有显著性差异 (前者携带A1等位基因的频率为 0 6 1,后者携带A1等位基因的频率为 0 31,P <0 0 5 ) ,携带A1等位基因更易形成海洛因依赖者 (比值比OR :3 47,P <0 0 5 )。各种行为类型的海洛因依赖者之间 ,基因型 (TaqIA多态性 )无显著性差异 (P >0 0 5 )。结论 :多巴胺D2 受体基因的TaqIA多态性与海洛因依赖相关连。多巴胺D2 受体基因TaqIA多态性与海洛因依赖者成瘾性的形成可能相关。这种基因位点特征可能与其他候选基因及环境因素共同作用 。

吗啡依赖大鼠脑多巴胺转运蛋白及D_2受体的研究

目的 观察吗啡依赖 (MD)大鼠脑多巴胺 (DA)系统的变化。方法 采用两隔室 (C1及C2 )模型训练大鼠对吗啡产生条件性位置偏爱 ,造成MD大鼠模型 ,用DA转运蛋白 (DAT)及DAD2 受体显像剂12 5I 甲苯 3β (4 碘苯基 )托烷 2 β 羟酸酯 (β CIT)、12 5I 左旋 3 碘 2 羟基 6 甲氧基 N[(1 乙基 2 吡咯烷 )甲基 ]苯酰胺 (IBZM)脑放射自显影、脑内放射性分布观察MD及对照组大鼠脑内D2 受体及DAT的变化。结果 条件性位置偏爱实验自第 6d后MD组大鼠由C1进入C2时间平均 (0 84±0 5 0 )min ,与对照组 (2 .40± 1.10 )min比较差异有显著性 (P <0 .0 5 ) ;放射自显影图像分析示 :12 5I β CITMD组纹状体 (ST) /小脑 (CB)及伏隔核 (NAC) /CB摄取比值分别为 4.76± 0 .92、2 .72± 0 96 ,与对照组 (5 .92± 0 .6 7、4.16± 0 .5 6 )比较差异有显著性 (P <0 .0 5 ) ;12 5I IBZM在MD组的ST/CB和NAC/CB摄取比值分别为 4.11± 0 .5 6、2 .6 4± 0 .2 5 ,明显低于对照组 (5 .43± 0 .74、3.49± 0 .6 5 ,P <0 0 5 ) ,脑内分布研究 (%ID/g脑组织湿重 )也证实MD组12 5I β CIT、12 5I IBZMST/CB摄取比值分别比对照组降低(2 1 6 8± 11.11) %和 (18.6 9± 9.97) %。结论 应用12 5I β CIT、12 5I IBZM能够敏感地反映MD?

多巴胺D_2受体显像剂Epidepride的合成及其^(131)I标记

以 3-甲氧基水杨酸为原料合成了 Epidepride[S- ( - ) - N- [( 1-乙基 - 2 -吡咯烷基 )甲基 ]- 5-碘 - 2 ,3-二甲氧基苯甲酰胺 ]及其标记前体 ( S- ( - ) - 5- (三正丁基锡 ) - N- [( 1-乙基 - 2 -吡咯烷基 )甲基 ]2 ,3-二甲氧基苯甲酰胺 ) ,并采用双氧水法对标记前体进行 131I标记 ,获得 131I- epidepride,标记率和放化纯度均大于 95%。13 1I- epidepride溶液体外稳定性好 ,4℃放置 15d放化纯度仍大于 90 %。131I- epide-pride与 D2 受体亲和力高 ,大鼠脑内纹状体与小脑的摄取比在 32 0 min时高达 2 37;在脑内纹状体的吸收可被 Spiperone完全阻断。因此 ,131I- epidepride有望成为多巴胺 D2 受体 SPECT显像剂。