微透析取样和微柱液相色谱电化学检测法测定大鼠脑纹状体中…

建立一个测定生物样本中５－羟色胺的灵敏方法。将微透析取样和微柱液相色谱电化学检测有机结合，建立灵敏的分析方法。箐容易地测定了自由活动大鼠脑纹状体透析液中ｆｇ－ｐｇ的５－羟色胺变化。本法对生物活体研究有很用。健康大鼠脑纹状体内５－羟色胺水平是相当稳定的。     

抗抑郁候选化合物GL-21对大鼠脑皮质中神经递质含量影响的研究

目的:研究抗抑郁候选化合物GL-21对大鼠脑皮质中神经递质去甲肾上腺素(NE)及5-羟色胺(5-HT)含量的影响。方法:采用微透析法取样和高效液相色谱法测定大鼠脑皮质中NE及5-HT的含量。结果:分别给大鼠GL-21 2,4和8 mg/kg后,可大幅增加大鼠脑皮质中神经递质NE及5-HT的含量(P<0.05 or P<0.01),且呈一定的剂量关系。结论:抗抑郁候选化合物GL-21可增加大脑皮质单胺类递质NE及5-HT含量。     

遍地金对大鼠脑突触体[3H]—5羟色胺重摄取抑制试验

目的 检测金丝桃属植物遍地金提取物对大鼠脑突触体5-羟色胺重摄取功能的抑制作用及其可作为抗抑郁药的潜在价值。方法 采用液闪仪测定[3H]标记的5-羟色胺与大鼠下丘脑组织悬液混合孵化后的CPM值作为重摄取量的评价指标。结果 遍地金提取物及St．John’s Wort提取物抑制5-羟色胺重摄取IC50分别为376．3μg／ml和515．18μg／ml。结论 遍地金提取物与st．John’s Wort提取物均对大鼠脑突触体5-羟色胺的重摄取有明显的抑制作用。     

脑康泰胶囊对血管性痴呆大鼠行为学的影响

目的：观察脑康泰胶囊对血管性痴呆(VD)大鼠学习记忆功能的影响，并探讨其相关机制。方法：制备VD模型，采用避暗法及水迷宫法评价脑康泰对VD模型大鼠学习记忆的影响，并用荧光分光光度法测定大鼠海马组织中5-羟色胺、多巴胺和去甲肾上腺素含量。结果：脑康泰可以明显改善VD大鼠的学习记忆功能，同时可不同程度增加VD大鼠海马组织中5-羟色胺、多巴胺和去甲肾上腺素含量。结论：脑康泰对VD大鼠学习记忆功能有一定的改善作用，其机制可能与提高脑组织中单胺类神经有关。     

HPLC-ECD法同时测定海洛因急性中毒大鼠不同脑区 中单胺类神经递质含量

目的:建立高效液相色谱-电化学检测器(HPLC-ECD)法同时测定大鼠伏隔核和纹状体两个不同脑区中单胺类神经递质多巴胺(DA)和5-羟色胺(5-HT)含量的方法,并对海洛因急性中毒大鼠不同脑区中单胺类神经递质的含量变化进行研究.方法:高效液相色谱采用QUATTRO C18色谱柱,以磷酸二氢钠-柠檬酸-辛烷磺酸钠缓冲液:...     

TMB-8抑制神经递质引起的单个脑细胞内游离钙的升高(英文)

目的:研究TMB-8对神经递质引起的单个脑细胞内游离钙升高的作用。方法:应用AR-CM-MIC阳离子测定系统测定游离大鼠单个脑细胞内钙离子浓度。结果:当细胞外液Ca~(2 )浓度为1.3mmol·L~(-1)时,TMB-8 30μmol·L~(-1)能降低谷氨酸,组织胺,5-羟色胺引起的脑[Ca~(2 )]_i浓度的升高。而当细胞外液无钙时,TMB-8能降低细胞内静息[Ca~(2 )]_i;TMB-8 10μmol·L~(-1)则几乎完全抑制了组织胺和5-羟色胺引起的脑[Ca~(2 )]_i升高作用。结论:TMB-8能降低谷氨酸,组织胺,5-羟色胺引起的脑[Ca~(2 )]_i升高。     

高效液相色谱-电化学法测定大鼠不同脑区的单胺类神经递质

目的:建立同时测定大鼠脑组织中单胺类神经递质去甲肾上腺素(NE)、多巴胺(DA)和5-羟色胺(5-HT)的高效液相色谱-电化学检测法(HPLC-ECD).方法:采用Diamonsil C18柱,以Na2HP04-枸橼酸-EDTA-庚烷磺酸钠-甲醇-水(80:40:2:7:32:89)为流动相,流速:1.2 ml/min.大鼠脑组织样品经高氯酸沉淀除去蛋白后,电化学检测脑内NE、DA和5-HT的含量.结果:脑组织中NE、5-HT的线性范围为0.50～10.00 ng,DA的线性范围为0.25～30.00ng.脑组织样品的相对回收率为91.7%～110.2%,日内、日间变异均小于15%.经初步研究,正常雄性SD大鼠不同脑区内NE、DA和5-HT的含量分别为伏隔核(508±203)、(3140±486)、(601±105)ng/g,腹侧被盖区(695±152)、(746±143)、(1049±222)ng/g,下丘脑(2032±351)、(332±236)、(847±218)ng/g,纹状体(790±205)、(5816±805)、(538±112)ng/g.结论:该方法具有准确、灵敏、样品制备简便等优点,可用于大鼠部分脑区内单胺类神经递质的分离测定.     

柱前衍生化液相色谱-质谱联用法测定大鼠血浆中5-羟色胺的浓度

目的:建立应用液相色谱-质谱联用(LC-MS/MS)测定大鼠血浆(包括富含血小板血浆)中5-羟色胺浓度的方法,并将其应用于感染后肠易激综合征模型大鼠体内5-HT的测定。方法:血浆样品在加入甲巯咪唑(内标)后用苯甲酰氯作为衍生试剂,以四硼酸钠为催化试剂,室温下进行柱前衍生。样品在甲醇沉淀蛋白后采用ESI电离源在正离子模式下检测,用Agilent Zorbax eclipse plus C18色谱柱,甲醇-水溶液为流动相洗脱,流速为1.0 ml·min^-1。结果:经衍生后5-HT在大鼠富含血小板血浆及血浆中其线性范围及定量限均符合测定要求,日内、日间精密度及基质效应均<15%;肠易激综合征大鼠血浆中游离5-HT相较正常组大鼠显著增高。结论:本方法快速、灵敏、专属性强且重现性好,可用于大鼠血浆中5-HT浓度的测定。     

高效液相色谱-电化学法测定大鼠不同脑区的单胺类神经递质

目的:建立同时测定大鼠脑组织中单胺类神经递质去甲肾上腺素(NE)、多巴胺(DA)和5-羟色胺(5-HT)的高效液相色谱-电化学检测法(HPLC-ECD).方法:采用Diamonsil C18柱,以Na2HP04-枸橼酸-EDTA-庚烷磺酸钠-甲醇-水(80:40:2:7:32:89)为流动相,流速:1.2 ml/min.大鼠脑组织样品经高氯酸沉淀除去蛋白后,电化学检测脑内NE、DA和5-HT的含量.结果:脑组织中NE、5-HT的线性范围为0.50～10.00 ng,DA的线性范围为0.25～30.00ng.脑组织样品的相对回收率为91.7%～110.2%,日内、日间变异均小于15%.经初步研究,正常雄性SD大鼠不同脑区内NE、DA和5-HT的含量分别为伏隔核(508±203)、(3140±486)、(601±105)ng/g,腹侧被盖区(695±152)、(746±143)、(1049±222)ng/g,下丘脑(2032±351)、(332±236)、(847±218)ng/g,纹状体(790±205)、(5816±805)、(538±112)ng/g.结论:该方法具有准确、灵敏、样品制备简便等优点,可用于大鼠部分脑区内单胺类神经递质的分离测定.     

HPLC-ECD法测定大鼠脑组织中单胺类神经递质的含量

目的:建立测定大鼠脑组织中的单胺类神经递质含量的方法。方法:采用高效液相色谱-电化学法,以2,5-二羟基苯甲酸为内标,测定大鼠大脑皮层、小脑、海马组织、下丘脑、嗅球中以去甲肾上腺素(NE)和5-羟色胺(5-HT)为代表的单胺类神经递质的含量。色谱柱为DIKMAC18,流动相为缓冲盐溶液(醋酸钠、庚烷磺酸钠、乙二胺四乙酸二钠和柠檬酸)-甲醇(梯度洗脱),流速为1.0 ml/min,工作电压为+0.7 V。结果:NE、5-HT的检测质量浓度线性范围分别为0.084⁴.2μg/ml(r=0.999 9)和0.0054.2μg/ml(r=0.999 9)和0.005⁰.25μg/ml(r=0.999 1),平均加样回收率分别为98.85%(RSD=2.89%,n=3)和101.5%(RSD=2.41%,n=3),日内(n=5)和日间(n=3)RSD均不大于3%;NE在小脑中的含量最低[(0.343±0.14)mg/g],在下丘脑中含量最高[(3.062±1.51)mg/g];5-HT在小脑中的含量最低[(0.059±0.04)mg/g],在大脑皮层中含量最高[(0.383±0.21)mg/g]。结论:本方法灵敏、简便、快速,可用于大鼠脑组织中NE、5-HT含量的测定。     

Long-term effects of postnatal aluminium exposure on acetylcholinesterase activity and biogenic amine neurotransmitters in rat brain

The long-term effects of early postnatal exposure to aluminium on acetyl choline esterase (AChE) activity and on biogenic amines were studied in different brain regions. The subjects were eight days old male Wistar rat pups. They were grouped into normal control and aluminium exposed groups. For aluminium exposure, the pups were gastric intubated with aluminium chloride (40 mg/Kg body weight) for two weeks. Control rats were given equal volumes of distilled water. After the treatment, they were rehabilitated for forty days. On the sixtieth day, the rats from both the groups were sacrificed and AChE activity, levels of dopamine, noradrenaline and serotonin were estimated in the cerebral cortex, hippocampus, septum, brainstem and striatum. In the aluminium exposed group: the AChE activity was significantly decreased in the hippocampus, septum, striatum and brainstem; serotonin levels were reduced by 20% in the cortex, hippocampus, septum and striatum; in brain stem, the serotonin level was decreased by 40%. A 60% reduction in noradrenaline levels was observed in the striatum whereas it was reduced by 25% in other regions except in hippocampus. Though dopamine levels were not altered in the cortex, septum and brainstem, they were reduced by 40% in the striatum. The study documents the long-term consequences of exposure to aluminium during the developmental periods.     

Serotonergic and Antiserotonergic Influences on Apomorphine-induced Stereotyped Behaviour

Abstract: The possible role of serotonin in modifying apomorphine-induced stereotyped behaviour was investigated by studying the effects of methysergide and 5-hydroxytryptophan on the threshold dosage of apomorphine required to induce stereotyped behaviour. The central serotonin antagonist methysergide potentiated apomorphine-induced stereotyped behaviour, and 5-hydroxytryptophan, the precursor of serotonin, inhibited apomorphine-induced stereotyped behaviour. These results suggest that serotonin may play a role in the balance of neurotransmitters within the striatum that influence movements.     

Evidence of serotonin involvement in the effect of morphine on dopamine metabolism in the rat nucleus accumbens but not in the striatum

Morphine-induced increase of dopamine metabolism in the striatum and nucleus accumbens was studied in rats treated with parachlorophenylalanine, an inhibitor of serotonin synthesis, or metergoline and mianserin, two serotonin antagonists. Morphine's effect in the nucleus accumbens, but not in the striatum, was significantly reduced by all the agents used to reduce serotonin transmission. It thus appears that part of the effect of morphine on dopamine metabolism in the nucleus accumbens is mediated by its ability to activate 5-HT function in this area.     

Striatal serotonin depletion facilitates rat egocentric learning via dopamine modulation

Egocentric spatial learning has been defined as the ability to navigate in an environment using only proprioceptive information, thereby performing a motor response based on one's own movement. This form of learning has been associated with the neural memory system, including the striatum body. Cerebral serotonin depletion induces better performance, both in tasks with strong egocentric components and in egocentric navigation in the Morris' maze. Based on this, we propose that the striatal serotonergic depletion must facilitate egocentric learning. Fifteen female Sprague Dawley rats weighing 250-350 g and maintained under standard conditions were chronically implanted with infusion cannulas for bilateral application of drugs into the striatum. The animals were evaluated for egocentric navigation using the Morris' maze, under different conditions: saline solution infusion, serotonin depletion by infusion of 5,7-Dihydroxytryptamine (25 microg of free base solved in 2.5 microl of ascorbic acid 1% in saline solution), infusion of mixed dopamine D(1) and D(2) receptor antagonists (0.5 microl/min during 5 min of mixed spiperone 20 microM and SCH23390 10 microM), or serotonin depletion and dopamine blockade simultaneously. Striatal serotonin depletion facilitated egocentric learning, which was demonstrated as shorter escape latencies and the display of a defined sequence of movements for reaching the platform. The facilitation was not observed under condition of simultaneous dopamine blockade. Striatal serotonin depletion produced a dopamine-dependent facilitation of egocentric learning. A role for serotonin in the inhibition of striatal-mediated learning strategies is proposed.     

Modulation by dopaminergic and serotonergic systems of cholinergic interneurons in nucleus accumbens and striatum

The acetylcholine turnover rate and the enzymatic activity of choline acetyltransferase were determined in the nucleus accumbens and striatum. Whereas both apomorphine and a serotonin agonist MK 212 led to a decrease in acetylcholine turnover rate, haloperidol showed the opposite effect in the nucleus accumbens and striatum, respectively. Dopamine and serotonin agonists induced a depression of the enzymatic activity but this effect was less pronounced than the effect on acetylcholine turnover rate. It is concluded that in the nucleus accumbens and striatum the cholinergic interneurons appear to be modulated by dopaminergic and serotonergic systems in an inhibitory manner.     

Acute effects of nomifensine on in vivo uptake and metabolism of dopamine, noradrenaline and serotonin in the rat brain

Nomifensine, in contrast to all other antidepressants, inhibits the neuronal uptake of dopamine. The effect of this drug (10 mg/kg intraperitoneally) on the metabolism of dopamine, serotonin and noradrenaline was studied in the rat brain. After 1.5 hours, nomifensine increased the concentrations of homovanillic acid (HVA) in corpus striatum and total (free and conjugated) 3-methoxy, 4-hydroxyphenylglycol (MOPEG) in mesencephalon, but had no effect on the 5-hydroxyindoleacetic acid (5-HIAA) in pons/medulla oblongata and mesencephalon. The effect was identical with that of desipramine (25 mg/kg) on MOPEG and of imipramine (25 mg/kg) on 5-HIAA. Two methods ordinarily used for estimating turnover rates of monoamines were compared: accumulation of acid metabolites after probenecid (measuring efflux of metabolites from the brain) and accumulation of monoamine precursors after decarboxylase inhibition (measuring amine synthesis). The efflux was reduced for 5-HIAA and MOPEG but increased for HVA after nomifensine. Imipramine had the same effect on 5-HIAA and desipramine on MOPEG. Desipramine decreased the efflux of HVA from corpus striatum. In contrast, nomifensine did not change the synthesis of noradrenaline and serotonin significantly. Imipramine reduced the synthesis of serotonin in pons/medulla oblongata. In corpus striatum nomifensine, unlike imipramine, increased the concentration of 5-HIAA and synthesis of serotonin in spite of a decrease in efflux, probably because of a secondary effect from the dopaminergic action. The conclusion was made that there were more than one compartment of monoamine metabolites. The antidepressants could to some extent lead to a shift in the metabolism to sites more distant to the transport mechanism.     

妊娠中期可卡因对小鼠的发育毒性

目的:探讨可卡因对小鼠妊娠中期的发育毒性,尤其是对脑发育的影响.方法:建立妊娠中期给药的小鼠动物模型,体重相近的妊娠母鼠被分为三组:(1)可卡因注射自由饮食组(COC);(2)盐水注射伴有饮食对照组(SPF),饮食参考体重相近、妊娠时间相同的COC组母鼠;(3)盐水注射自由饮食组(SAL).从妊娠第8天(E8)至第12天(E12)给药,记录母鼠、胎鼠和仔鼠的各项生理指标,并用HPLC分析各组胎鼠纹状体中多巴胺、5-HT含量的变化.结果:尽管COC和 SPF组母鼠与 SAL组母鼠相比摄食量少,体重增加量少,但E17 天取材时,仅COC组胎鼠表现为脑和纹状体重量低;COC组仔鼠生后第 1天(P1)双顶径(BPD)也小于其它两组仔鼠.此外,COC组胎鼠表现出脑/体重比的降低,说明宫内暴露可卡因引起的胎鼠的发育迟缓是一个不平衡过程,脑组织的受累比其它组织严重.神经递质分析和组织学分析表明 COC组胎鼠脑内多巴胺和5-羟色胺的水平增高,肝脏呈现出形态学改变.结论:妊娠中期暴露可卡因可引起胎鼠宫内发育迟缓,尤其是脑发育迟缓.单纯母体营养不良在宫内暴露可卡因引起的后代发育迟缓过程中不能起决定性作用,而可能是药物直接作用的结果.     

Hydroxyl Radical Formation Following Methamphetamine Administration to Rats

Abstract: Administration of neurotoxic doses of methamphetamine (8 mg/kg, intraperitoneally x 4 times, at 2 hr intervals) caused a significant decrease in dopamine and 3,4-dihydroxyphenylacetic acid and an increase in 3-methoxytyramine levels in the striatum along with a decrease in serotonin and 5-hydroxyindoleacetic acid levels in the striatum and hippocampus. In addition, the methamphetamine treatment caused an increase in rat rectal temperature. Intraventricular injection of salicylate 105 min. after the last injection of methamphetamine produced an increase in 2,3- and 2,5-dihydroxybenzoic acid in the striatum and hippocampus. Moreover, the ratio of 2,3-dihydroxybenzoic acid to salicylate was significantly increased in the striatum, but not in the hippocampus. These results indicate that the hydroxyl radical may play an important role in methamphetamine-induced neurotoxicity in rat striatum and that its formation may be the result of methamphetamine-induced release of dopamine.     

Short-term effects of ether, equithesin and droperidol/fentanyl on catecholamine and indolamine metabolism in the brain of the rat

Levels of biogenic amines and their major metabolites were measured in the frontal cortex, dorsal striatum (caudate nucleus) and ventral striatum (nucleus accumbens and olfactory tubercle) of rats which had received anaesthetic or analgesic drugs or no treatment, shortly before decapitation. Apart from a reduced level of homovanillic acid in the ventral striatum after ether, no differences were observed between ether- or Equithesin-treated and untreated animals in the levels of dopamine, dihydroxyphenylacetic acid, homovanillic acid, 3-methoxytyramine, noradrenaline, serotonin or 5-hydroxyindoleacetic acid. The neuroleptic analgesic droperidol/fentanyl, on the other hand, increased the levels of dihydroxyphenylacetic acid in the frontal cortex and dorsal and ventral striatum and of homovanillic acid in the ventral striatum; additionally, a reduced level of serotonin was observed in the frontal cortex. It is concluded that both ether and Equithesin can be used as short-term anaesthetics prior to sacrificing rats, when the levels of biogenic amines are to be analyzed in the frontal cortex or ventral or dorsal striatum.