NMDA受体在大鼠实验性脑震荡组织中表达研究

脑震荡是一种轻型颅脑损伤，临床症状多表现为短暂的意识障碍，其机制尚未完全阐明。本探讨N—甲基—D—天冬氨酸受体(N—methyl—D—aspartate receptor，NMDAR)在脑震荡发生机制中的作用。     

5-羟色胺异常在自杀行为中的作用

近 2 0多年来 ,通过对自杀行为的大量研究发现 ,5 -羟色胺 (5 -HT)功能降低与自杀行为有密切关系[1] 。 5 -HT在自杀中起何种角色 ,还有许多问题值得探讨。1　 5 -HT系统5 -HT系统是已知的脑内最大的一个神经元系统。 5 -HT能神经元起源于脑干的背内中缝核 ,其神经末梢几乎投射到所有脑内的初级靶目标 ,包括黑质 ,下丘脑、丘脑、杏仁核、海马区、尾核、壳核和伏膈核及大脑皮层区域如额叶、枕叶、岛区、顶叶、颞叶和小脑皮层。这表明其结构可以对中枢神经系统多个区域的功能同时施加影响。 5 -HT神经递质在不同区域、不同受体亚型、其对…     

实验性颅脑损伤脑组织5-羟色胺和钙离子含量变化的研究

目的:研究脑损伤后脑内5-羟色胺(5-HT)和钙离子(Ca~(2 ))含量变化规律及其对脑的继发性损害。方法:采用荧光分光光度法对大鼠脑损伤后不同时间脑组织5-HT及Ca~(2 )含量进行检测,同时测量脑含水量并作病理观察。结果:在脑损伤后4h,脑组织中5-HT及Ca~(2 )含量显著增高,伤后8h仍维持在高水平,伤后4h脑含水量递增,电镜观察神经细胞受损逐渐加重。结论:5-HT的过度合成和释放可使脑组织内Ca~(2 )集聚增加,造成神经细胞严重损伤,并引起和加重继发性脑损伤。     

5-羟色胺受体与抑郁症

国外报道抑郁症的男性终生患病率为 5 %～12 % ,女性为 10 %～ 2 0 % ,其中 5 0 %～ 85 %可反复发作 ;每年有 15 %的抑郁症患者自杀[1] 。 5 羟色胺受体 (5 ＨＴＲ)在抑郁症的病因和抗抑郁剂的药理机制中发挥着重要作用。人类至少存在 7种 5 ＨＴＲ即 :5 ＨＴ1Ｒ、5 ＨＴ2 Ｒ、5 ＨＴ3Ｒ、5 ＨＴ4 Ｒ、5 ＨＴ5Ｒ、5 ＨＴ6 Ｒ、5 ＨＴ7Ｒ ,且大部分已被克隆 ,7种类型又进一步分为若干亚型。哪些5 ＨＴＲ亚型与抑郁症及抗抑郁剂的作用有关还远未完全清楚 ,可能为 5 ＨＴ1Ａ Ｒ、5 ＨＴ1ＣＲ、5 ＨＴ2 Ｒ、5 ＨＴ3Ｒ。作者单位 …     

实验性Alzheimer模型鼠脑组织5—羟色胺含量改变的研究

制做Alzheimer病(AD)大鼠模型,检测不同时期、不同脑区5-羟色胺(5-HT)含量变化。结果表明:AD鼠在30d时就表现出海马及丘脑5-HT含量的明显下降。据此推测可能是胆碱能系统损害能直接影响5-HT系统代谢功能,胆碱能系统对5-HT系统的功能和代谢有调节作用。     

5-羟色胺受体的研究现状

５羟色胺（５ＨＴ）既是一种神经递质，又是一种血管活性物质，在中枢神经系统和周围组织中起着多种生理作用。有研究表明，５ＨＴ在中枢神经系统中的分布十分广泛，参与了各种精神活动的调节［１］，如与焦虑症、强迫症、孤独症、情感性精神障碍、精神分裂症以及酒...     

5-羟色胺能系统在抑郁症中的研究进展

抑郁症是一组严重影响人们生活质量的情感障碍疾病。世界卫生组织估计，按如今发展速度，抑郁症将在2020年成为人类第二大常见的致残性疾病。抑郁症病因复杂，但单胺类神经递质，特别是5-羟色胺（5-HT）在抑郁症治疗中的地位却有目共睹，     

5-羟色胺异常在自杀行为中的作用

本文综述了5-羟色胺(5-HT)功能低下与自杀行为的关系，并就5-HT在自杀行为中的作用做了客观的评价。     

急性脑卒中患者血浆5-羟色胺等物质改变的临床意义

目的：探讨脑卒中患者血浆５－羟色胺及其相关物质的变化与临床的关系。方法;用荧光法测定５０例急性脑卒中患者和５０例健康者血浆５－ＨＴ,５－羟吲哚乙酸,去甲肾上腺素水平。结果：急性脑卒中血浆５－ＨＴ,５－ＨＩＡＡ,ＮＥ水平显著高于健康组,脑出血组５－ＨＴ升高更为显著,脑卒中死亡患者５－ＨＴ坑于存活者。     

The stimulus-induced release of unmetabolized 5-hydroxytryptamine from superfused rat brain synaptosomes

A number of existing techniques have been modified to produce an improved technique for examining the depolarization-induced release of unmetabolized 5-hydroxytryptamine (5-HT) from drug-free superfused synaptosomes. Synaptosomes which have been pre-loaded with [3H]5-HT are set up in perfusion chambers and continuously perfused with medium. Serial samples of effluent perfusate are collected on ice and the released 5-HT and 5-hydroxy-indole acetic acid (5-HIAA) are separated by ion exchange chromatography. The technique provides reproducible Ca2+-dependent responses to K+ depolarization in the absence of monoamineoxidase inhibition and free from the interference of re-uptake. The advantages of the use of the system in examining transmitter release and its modulation is discussed.     

Urethane reduces contraction to 5-hydroxytryptamine (5-HT) and enhances the action of the 5-HT antagonist ketanserin on the rat thoracic aortic ring

Summary The general anesthetic urethane (ethyl carbamate) is widely used in electrophysiological in vivo experiments. However, its pharmacological effects are poorly understood. Here, the effects of urethane on in vitro contractile responses of the rat thoracic aortic ring preparation were investigated. Bath application of 5-HT produced a concentration-dependent contractile response (EC₅₀=4.3 × 10^–6M). Urethane (11.2 mM=1mg/ml) shifted the concentration — response curve (CRC) for 5-HT to the right (EC₅₀=1.7 × 10^–5M) and decreased the maximal contraction by 30.8%. The CRC for NA (EC₅₀=7.2 × 10^–9M) was also shifted to the right by urethane (EC₅₀=1.4 × 10^–8M), but the shift of the 5-HT-CRC was twice that of the NA-CRC (3.95 vs. 1.95). The CRC to KCl was shifted rightwards only slightly by urethane (ratio 1.27) and the maximal contraction to KCl was not affected. The CRC to replacement of CaCl₂ (0.1 – 10 mM) to KCl-depolarized vessels in a Ca²⁺ -free Krebs solution was unaffected by urethane. Ketanserin (10^–9M) antagonized the contraction to 5-HT, and a combination of ketanserin and urethane was markedly more effective than either drug alone, decreasing the maximal contraction by 58%. Antagonism of NA contraction by prazosin (5×10^–8M) was not increased by addition of urethane.The urethane dose used here approximates blood and brain concentrations required to produce anesthetic effects in mammals. It is possible that reductions in 5-HT transmission and, to a lesser extent, in NA transmission, but not blockade of Ca²⁺ or K⁺ channels, may contribute to the anesthetic effect of urethane. In addition, the action of the selective 5-HT₂ antagonist ketanserin is clearly altered by urethane. These findings are important to consider when urethane is used for in vivo neurophysiological investigations, particularly when 5-HT mechanisms are involved.     

5-HT2C受体在癫患者脑组织的表达

目的研究5-羟色胺2C受体(5-HT2C受体)在癫患者脑组织的表达,探索其临床意义。方法用免疫组化方法检测46例癫患者术后脑组织5-HT2C受体的表达,研究比较不同部位不同病程脑组织表达。结果癫患者额叶脑组织5-HT2C受体的含量较颞叶海马明显增高,长病程组表达低于短病程组。结论 5-HT2C受体可能参与了癫的发病机制,改变5-HT2C受体的表达有望成为癫新的治疗靶点。     

Time-dependent effects of actinomycin S3 on sleep and brain concentrations of 5-hydroxytryptamine in the rat

Changes in the sleep pattern were investigated in rats given actinomycin S3 (AcS3, 0.25 mg/kg, intraventricularly), an inhibitor of RNA synthesis, at 0000, 0600, 1200, and 1800. The amounts of slow-wave (SS) and paradoxical sleep (PS) were increased during the dark period (1800 to 0600) in the groups treated at 0000, 0600, and 1200. In the 1800 injected group, PS was decreased. 5-Hydroxytryptamine (5-HT) was determined in the 0600 injected group. The 5-HT concentration in the AcS3-treated group was twofold higher than in the control group at 1800 (12 h after administration) in the cerebral cortex and lower brain stem but returned to control values at 0000 (18 h after) while sleep time continued to increase. Thus, AcS3 affected the circadian rhythm of the sleep-wake cycle. The increase of sleep time in the dark period was independent of changes in brain 5-HT content.     

Effect of acute administration of morphine on newly synthesized 5-hydroxytryptamine in spinal cord of the rat

The effect of morphine (10 mg/kg, s.c.) on the rate of [³H]5-HT synthesis in brain and spinal cord following intravenous injection of [³H]tryptophan was studied in the rat.

(1) In the spinal cord morphine induced an increase in [³H]TRP uptake which was significant 30 and 60 min after the injection, and a clear enhancement of the formation of [³H]5-HT which was significant 15 min after the injection and which peaked at 30 min.

In the forebrain, the increase in [³H]TRP accumulation was significant as early as 15 min after morphine. At this time, the rate of 5-HT synthesis was not modified, but it was significantly increased 30 and 60 min after the injection.

(2) Increases in [³H]5-HT synthesis rate were suppressed by naloxone (1 mg/kg, i.m.). However this narcotic antagonist did not significantly reduce the increased accumulation of [³H]TRP in brain and spinal cord due to morphine treatment.

These results demonstrate that morphine induces a fast and marked increase in 5-HT synthesis, and suggest that this increase is only partly related to an increase in the availability of tryptophan to the central nervous system.These results are in good agreement with recent investigations showing the involvement of the raphe-spinal system in morphine analgesia.     

Distribution of serotonin 5-HT2A and 5-HT7 receptors in the Onuf''s nucleus of the rat spinal cord

BACKGROUND: Motoneurons from the Onuf's nucleus of the spinal cord, which innervate the striated muscle of the pelvic floor, play an important role in erection, ejaculation, and urine control. Serotonin (5-hydroxytryptamine, 5-HT) regulates motoneuron activity from the Onuf's nucleus of the spinal cord.However, few studies exist that describe 5-HT receptor distribution in the Onuf's nucleus. In addition, the nature of the effects of 5-HT receptor on the innervating striated muscle of the pelvic floor is controversial.OBJECTIVE: To investigate the distribution of serotonin 5-HT2A and 5-HT7 receptors in motoneurons of Onuf's nucleus in the spinal cord of male rats, and to analyze the relationship of 5-HT2A and 5-H7 receptors to central modulation of urogenital function.DESIGN, TIME AND SETTING: The neural morphology experiment was performed at the Ultramicrostructure Laboratory of Reproductive Medicine, Basic Medical College, Chongqing Medical University, China from April to December 2007.MATERIALS: Ten adult, Sprague Dawley rats (eight males and two females) were randomly divided into a gender control group (n = 4,50% male and 50% female) and a retrograde tracing group (n = 6, 100% male).Recombinant pseudorabies virus (PRV-152) was provided by Professor LW Enquist from Princeton University, USA. Rabbit anti-5-HT2A and 5-HT7 receptor antibodies were purchased from Diasorin, France.METHODS: In the gender control group, the spinal L5-6segments were harvested, sliced, and then incubated antibodies specific against 5-HT2A or 5-HT7 receptors for immunohistochemical staining. In the retrograde tracing group, PRV-152 was separately injected into the right ischiocavernosus (ischiocavernosus subgroup,n = 3) and the fight external urethral sphincter (external urethral sphincter subgroup, n = 3). Four days after injection, L5-6 segments were harvested, sliced, and incubated with antibodies specific against 5-HT2A or 5-HT7 receptors for double-labeling immunofluoresccnce staining.MAIN OUTCOME MEASURES: Distribution analysis of 5-HT2A and 5-Ht7 receptors in Onuf's nucleus utilizing optical or laser confocal microscopy.RESULTS: 5-HT2A receptor immunoreactivity was revealed primarily in the medial region of the dorsolateral nucleus of Onuf's nucleus. 5-HT7 receptor expression was observed in the lateral part of the dorsolateral nucleus. 5-HT2A and 5-HT7 receptor expressions in the Onuf's nucleus were significantly greater in male rats, compared to female rats. Double-labeling immunofluorescence demonstrated that 5-HT2A receptors were distributed primarily in the surrounding motoneurons innervating the ischiocavernosus, and 5-HT7 receptors were primarily expressed in motoneurons innervating the external urethral sphincter.CONCLUSION: Motoneurons innervating the ischiocavernosus and external urethral sphincter are located primarily in the medial and lateral region of the dorsolateral nucleus of L5-6 segments. The 5-HT2A receptor-innervating ischincavernosus may be preferentially involved in the regulation of sexual reflex, and the 5-HT7 receptor-innervating external urethral sphincter may mainly join in regulating micturition reflex.     

Effects of short-term lithium administration on tryptophan levels and 5-hydroxytryptamine synthesis in whole brain and brain regions in rats

Summary The effects of short-term lithium administration on tryptophan levels and 5-hydroxytryptamine (5-HT) synthesis in whole brain and brain regions in rats were studied. Short-term lithium administration was found to increase whole brain tryptophan levels without affecting whole brain 5-HT synthesis. However, the increase of tryptophan varied between various brain regions, which may possibly be due to differences in the synaptosomal uptake of tryptophan between brain regions. In the striatum, where the tryptophan increase was most pronounced, an increase in 5-HT synthesis was found too. These latter findings suggest that the increase in 5-HT synthesis might be due to an increase in tryptophan availability.     

Variation in response to stimulation of central 5-hydroxytryptamine mechanisms in two strains of albino rat

The responses of neurons in the fronto-parietal cortex to iontophoretically applied 5-hydroxytryptamine (5-HT) and to stimulation of the nucleus raphe medianus were determined and compared in Wistar and Sprague-Dawley (SD) rats. In the Wistar strain there were many more excitatory responses to both 5-HT and raphe stimulation than in the SD rats. The duration of the excitatory responses to stimulation was significantly greater in the Wistars than in SD rats and the duration of inhibitory effects significantly less. These results may help to explain divergent findings in different laboratories concerning the action of 5-HT in the cerebral cortex. We were also able to demonstrate a difference in the behavioral consequences of central 5-HT receptor activation between the two strains. Following administration of the precursor, 5-hydroxytryptophan, Wistar rats showed a much greater incidence of ‘wet dog shake’ responses than SD rats, but the SD strain displayed a more severe tremor.     

Rat brain concentrations of 5-hydroxytryptamine following acute and chronic administration of MAO-inhibiting antidepressants

1. Groups of male Sprague-Dawley rats were injected once daily with phenelzine (15 mg/kg) or tranylcypromine (10 mg/kg) and killed 6 h after drug administration on days 1, 2, 8 and 19.

2. Brains were analyzed for MAO activity by a radiochemical procedure and for 5-HT concen- trations by an electron-capture gas Chromatographic procedure.

3. Both drugs affected 5-HT concentrations in a similar manner—a significant increase of 5-HT over control levels by day 1, with levels still increasing between days 8 and 19, having attained concentrations approximately 5 times control values by day 19.     

Distribution of serotonin 5-HT2A and 5-HT7 receptors in the Onuf’s nucleus of the rat spinal cord*★

BACKGROUND：Motoneurons from the Onuf’s nucleus of the spinal cord, which innervate the striated muscle of the pelvic floor, play an important role in erection, ejaculation, and urine control. Serotonin （5-hydroxytryptamine, 5-HT） regulates motoneuron activity from the Onuf’s nucleus of the spinal cord. However, few studies exist that describe 5-HT receptor distribution in the Onuf’s nucleus. In addition, the nature of the effects of 5-HT receptor on the innervating striated muscle of the pelvic floor is controversial. OBJECTIVE： To investigate the distribution of serotonin 5-HT2A and 5-HT7 receptors in motoneurons of Onuf’s nucleus in the spinal cord of male rats, and to analyze the relationship of 5-HT2A and 5-HT7 receptor to central modulation of urogenital function. DESIGN, TIME AND SETTING： The neural morphology experiment was performed at the Ultramicro-structure Laboratory of Reproductive Medicine, Basic Medical College, Chongqing Medical University, China from April to December 2007. MATERIALS： Ten adult, Sprague Dawley rats （eight males and two females） were randomly divided into gender control group （n = 4, 50% male and 50% female） and a retrograde tracing group （n = 6, 100% male） Recombinant pseudorabies virus （PRV-152） was provided by Professor LW Enquist from Princeton University, USA. Rabbit anti-5-HT2A and 5-HT7 receptor antibodies were purchased from Diasorin, France. METHODS： In the gender control group, the spinal L5-6 segments were harvested, sliced, and then incubate antibodies specific against 5-HT2A or 5-HT7 receptors for immunohistochemical staining. In the retrograde tracing group, PRV-152 was separately injected into the right ischiocavernosus （ischiocavernosus subgroup, n = 3） and the right external urethral sphincter （external urethral sphincter subgroup, n = 3）. Four days after injection, L5-6 segments were harvested, sliced, and incubated with antibodies specific against 5-HT2A or 5-HT7 receptors for double-labeling immunofluorescence stain