首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The quantitative estimation of total dopamine (DA), noradrenaline (NE), serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) content in the whole brain tissue of normal Nile grass rat, Arvicanthis niloticus, gives and average of 631 +/- 12 ng DA/g, 366 +/- 12 ng NE/g, 617 +/- 15 ng 5-HT/g and 431 +/- 10 ng 5-HIAA/g fresh brain tissue. The effect of barbitone sodium and thiopental sodium on the total DA, NE, 5-HT and 5-HIAA content in the brain tissue of the Nile grass rat, Arvicanthis niloticus, was studied. The total DA, NE, 5-HT and 5-HIAA contents were determined 5 hr after i.p. injection of different doses of barbitone sodium (20, 40 and 80 mg/ml/100 g body wt) and thiopental sodium (5, 10 and 20 mg/ml/100 g body wt). The effect of different time intervals (1, 10, 30 min, 1, 2.5, 5, 8, 16, 24 and 48 hr) on the total brain DA, NE, 5-HT and 5-HIAA content was investigated after i.p. injection of 40 mg of barbitone sodium and 10 mg of thiopental sodium/ml/100 g body wt. Both barbitone sodium and thiopental sodium caused an increase in DA, NE and 5-HT content and a decrease in 5-HIAA content in the brain tissue of Arvicanthis niloticus. The increase in the whole brain contents of DA, NE and 5-HT after the administration of barbitone sodium and thiopental sodium may be due either to inhibition of transmitter release by an action at the monoamine nerve terminal or to effects causing a decrease in nerve impulse flow. On the other hand, the decrease in 5-HIAA may be due to the decrease in the turnover of 5-HT.  相似文献   

2.
The total ACh content and AChE activity were determined 1 hr after the i.p. injection of different doses of thiopental sodium (5, 10 and 20 mg/ml/100 g body wt) and barbitone sodium (20, 40 and 80 mg/ml/100 g body wt). The effect of different time intervals (1 min, 10 min, 30 min, 1 hr, 2.5 hr, 5 hr, 8 hr, 12 hr, 24 hr and 48 hr) on the total ACh content and AChE activity was investigated after i.p. injection of 10 mg thiopental sodium and 40 mg barbitone sodium/ml/100 g body wt. Both thiopental sodium and barbitone sodium increased the total ACh content in the brain tissue of Arvicanthis niloticus. Both drugs inhibited the brain AChE activity. It is thought that the increase in the total ACh content in the brain tissue of Arvicanthis niloticus may be due to a decrease in the release of ACh from the neuronal tissue and a decrease in AChE activity.  相似文献   

3.
目的通过对吗啡诱导的躯体依赖与精神依赖两种大鼠模型脑内单胺类递质水平的比较,探讨其在吗啡依赖形成中的作用。方法采用剂量递增法复制吗啡依赖大鼠模型,然后用纳洛酮催促,引起躯体戒断症状。连续给予吗啡(5mg/kg,ip)6d,引起大鼠产生显著的条件性位置偏爱效应。脑组织去甲肾上腺素(NE)、5-羟色胺(5-HT)和多巴胺(DA)含量采用荧光分光光度法测定。结果吗啡依赖大鼠催促戒断后脑内NE和5-HT水平明显升高,DA水平下降。吗啡在引起大鼠明显位置偏爱的同时,使大鼠脑内DA和5-HT水平显著升高,NE无明显改变。结论吗啡依赖的形成和戒断与脑内单胺神经递质有密切关系,吗啡依赖的躯体戒断症状与NE升高有关,而吗啡诱导的精神依赖则与脑内DA水平升高有关。  相似文献   

4.
摘要 目的:研究臭椿生物碱canthin-6-one对小鼠的镇静催眠作用。方法:选昆明小鼠随机分为空白组、地西泮阳性药物组、canthin-6-one低、中、高给药组(5、10、20 mg?kg-1),采用阈上剂量和阈下剂量戊巴比妥钠诱导小鼠睡眠,记录入睡小鼠比例、睡眠潜伏期和睡眠持续时间。此外,酶联免疫法测定小鼠脑组织中5-HT、NE、DA和GABA含量。结果:中、高剂量canthin-6-one可使小鼠的站立次数和自主活动次数均明显减少(P<0.05),可使阈上剂量戊巴比妥钠诱导的小鼠的睡眠潜伏期缩短(P<0.05);各剂量组可使阈下剂量戊巴比妥钠诱导的小鼠入睡率提高(P<0.05)。此外,中、高剂量canthin-6-one也可降低小鼠脑组织中5-HT和NE含量,增加GABA含量(P<0.05),对DA的含量有影响,但无统计学意义(P>0.05)。结论:Canthin-6-one有明显的协同戊巴比妥钠改善睡眠作用,其作用与相关神经递质(5-HT、NE、GABA)具有密切关系。  相似文献   

5.
The purpose of the present study was to examine the effects of an acute dose of the dual dopamine (DA) and norepinephrine (NE) reuptake inhibitor bupropion (Bup) on brain (T(brain)), body core (T(core)), and tail skin (T(tail)) temperature in freely moving rats and to simultaneously monitor the extracellular neurotransmitter concentrations in the preoptic area and anterior hypothalamus (PO/AH). A microdialysis probe was inserted in the PO/AH, and samples for NE, DA, and serotonin (5-HT) were collected every 20 min before and after the injection of 17 mg/kg of Bup, for a total sampling time of 180 min. T(core) was monitored using a biotelemetry system. T(brain) and T(tail), an index of heat loss response, were also measured. Both NE and DA levels in the PO/AH significantly increased after Bup injection compared with the baseline levels, reaching approximately 450 and 230%, respectively, 40 min after injection. There was no effect on 5-HT release. The neurotransmitter changes were accompanied by a significant decrease in T(tail) and an increase in both T(brain) and T(core) compared with the baseline levels. The present results demonstrate that inhibition of NE and DA reuptake suppresses heat loss mechanisms and elevates T(brain) and T(core) in freely moving rats.  相似文献   

6.
The effect of chronic treatment with tyroxine (T4) or propylthiouracile (PTU) on the turnover of norepinephrine (NE), dopamine (DA) and 5-hydroxytryptamine (5-HT) has been studied in various areas of the rat brain (brain stem, hypothalamus, striatum and "rest of the brain"). The turnover of NE and DA was determined by the decay in endogenous levels after inhibition of tyrosine hydroxylase by alpha-methylparatyrosine and the turnover of 5-HT was evaluated by the initial accumulation of endogenous 5-HT after inhibition of monoamine oxydase by pargyline. T4 treatment accelerated the release of DA from the striatum but had no significant effects on NA release in the various cerebral areas : nevertheless the NE endogenous level was significantly reduced in the brain stem. PTU treatment delayed the release of DA and NA only from the "rest of the brain". Concerning 5-HT, the only significant variation was observed in the hypothalamus of PTU-treated rats and implied increased turnover. The possible relations between the changes in cerebral monoamines turnover and the behavioural alterations which are observed in thyroid disfunction are discussed.  相似文献   

7.
The neuroleptic drug, chlorpromazine (CPZ) has been shown to exert its antipsychotic effect by blocking post synaptic dopamine receptors. However, its effect on steady state levels of monoamines is still in discrepancy. In the present study, CPZ (4 mg/kg body weight) was administered intraperitoneally to adult Wistar rats chronically for 75 days and the levels of norepinephrine (NE), dopamine (DA) and 5-hydroxytryptamine (5-HT) were assayed in various brain regions by high performance liquid chromatography (HPLC). After the experimental period body and brain weights were not statistically different from controls. NE and 5-HT levels were increased only in hippocampus by 15% (p<0.01) and 16% (p<0.01) respectively. DA levels were consistently increased in cortex by 39% (p<0.001), striatum-accumbens by 18% (p<0.01), hippocampus by 27% (p<0.01), hypothalamus by 34% (p<0.001), cerebellum by 36% (p<0.001) and brainstem by 40% (p<0.001) in CPZ treated rats compared to controls. The results suggest that chronic CPZ administration increases DA levels in almost all regions of brain and reflect the ability of CPZ to preferentially interfere with synaptic transmission mediated by DA in brain. It also suggests that this increase in DA might be responsible for certain side effects seen in patients after chronic CPZ treatment.  相似文献   

8.
In addition to their well recognized activity in blocking uptake of biogenic amines, tricyclic antidepressants have recently been shown, with chronic treatment, to alter neurotransmitter receptor sensitivity. In this study, the responsiveness of facial motoneurons to norepinephrine (NE) and serotonin (5-HT) was assessed with single unit recording and microiontophoretic techniques. Treatment of rats with daily intraperitoneal injections of several clinically effective tricyclics for 14–20 days was found to enhance responses to NE, 5-HT, and to an intravenously administered 5-HT agonist, 5-MeODMT. These changes in sensitivity were not seen in animals chronically treated with saline, chlorpromazine, or fluoxetine, and thus appear specific to antidepressants. Acute effects of tricyclics on NE and 5-HT responses were variable, dependent on the specific drug tested, and appear to have no necessary relation to the pronounced sensitization produced by chronic treatment.  相似文献   

9.
The effect of 5-hydroxytryptamine (5-HT) alteration on brain dopamine (DA), norepinephrine (NE), beta-endorphin (beta E) and immunoreactive insulin (IRI) was studied in Sprague-Dawley diabetic and control rats. Diabetes was induced using alloxan (45 mg/kg), 15 days prior to sacrificing. Both control and diabetic animals were treated with either p-chlorophenylalanine (PCPA, 300 mg/kg) 3 days prior to sacrificing or fluoxetine (10 mg/kg) twice daily for 3 days. PCPA treatment significantly decreased brain content of 5-HT and 5-hydroxyindole acetic acid (5-HIAA) while it caused significant increase and decrease in brain beta E and insulin levels, respectively, in both normal and diabetic rat. Meanwhile, the administration of fluoxetine resulted in significant increase in brain content of 5-HT, DA, NE and insulin but significant decline of beta E in diabetic and saline control rats. The results of this experiment indicate that 5-HT may be regulating both beta E and insulin regardless of the availability of pancreatic insulin.  相似文献   

10.
The conditions reported by Toru and Aprison (4) for extracting ACh in specific brain areas were tested to determine whether 5-HT, NE, and dopamine were also extracted quantitatively. It was found that the extraction solution used in brain ACh determinations, 15% 1N formic acid plus 85% acetone (vv), was also excellent for extraction of NE, 5-HT, and dopamine from different brain areas. Experimental conditions are given for the microdetermination of all three biogenic amines in such a single extract of a specific rat brain area. The methods are based on previously published fluorometric methods; these have been scaled down or modified slightly to permit analyses of small aliquots. The concentration of 5-HT, NE, and dopamine in the telencephalon, diencephalon plus mesencephalon, pons plus medulla oblongata, and cerebellum of the rat are also reported using the described micromethods after extraction with 15% 1 N formic acid plus 85% acetone (vv).  相似文献   

11.
Abstract: In this study, we compare the electrically evoked, somatodendritic release of dopamine (DA) with axonal release of serotonin (5-HT) in the substantia nigra (SN) and ventral tegmental area (VTA) in vitro by using fast-scan cyclic voltammetry with carbon-fibre microelectrodes. Furthermore, we have examined transmitter release in these regions in guinea-pig compared with rat. Somatodendritic DA was released, as shown previously, in guinea-pig VTA, SN pars compacta (SNc), and occasionally in SN pars reticulata (SNr). 5-HT was rarely released, except in SNr, where nonetheless it only contributed to <30% of amine signals. In rat midbrain, somatodendritic DA release was evoked to a similar extent as in guinea-pig. However, a clear species difference was apparent; i.e., 5-HT and DA were detected equally in rat SNc, whereas in rat SNr, 5-HT was the predominant transmitter detected. Nevertheless, electrically evoked extracellular concentrations of 5-HT in SNc and SNr were, respectively, seven- and fourfold less than DA in SNc. 5-HT release was low in all regions in neonatal rat slices before the maturation of 5-HT terminals. Hence, axonal 5-HT transmission in midbrain exhibits both species and site selectivity. Moreover, whereas somatodendritic DA release is conventionally regarded as modest compared with axon terminal release in striatum, somatodendritic DA release can result in significantly greater extracellular levels than a transmitter released from axon terminals in the same locality.  相似文献   

12.
调心滋肾中药组方对老年痴呆大鼠海马神经递质的影响   总被引:2,自引:0,他引:2  
目的: 建立痴呆大鼠模型,观察调心滋肾中药组方对大鼠海马神经递质含量的影响.方法: 选用体重300~350 g的健康成年雄性Wistar大鼠, 参照大鼠脑立体定位图谱,双侧注入Ibotenic acid(IA)破坏大鼠Meynert基底核,建立痴呆大鼠模型.造模7 d后应用调心方、滋肾方和调心滋肾方治疗各20 d后,分光光度法检测海马乙酰胆碱含量,高效液相色谱法检测5-羟色胺和去甲肾上腺素的含量.结果: 经调心方、滋肾方和调心滋肾方治疗后,痴呆模型大鼠海马乙酰胆碱、5-羟色胺和去甲肾上腺素含量均明显提高.结论: 经调心方、滋肾方和调心滋肾方对痴呆模型大鼠海马降低的乙酰胆碱、5-羟色胺和去甲肾上腺素有上调作用.  相似文献   

13.
The effect of subcutaneous injections of saline (0.9% NaCl, 10–40 μl/g b. wt) to 5- and 20-day old rats on the concentrations of tyrosine (Tyr) and tryptophan (Trp) in the serum and the brain and on the levels of biogenic amines and their metabolites in the developing brain at 6 h p.i. is described. At day 5 the concentration of Tyr in the blood was decreased (dose-dependent), but the brain concentrations of Tyr and of its amine-metabolites, dopamine (DA), norepinephrine (NE), homovanillic acid (HVA) and dihydroxyphenylacetate (DOPAC) were unaffected. In contrast, in the 20-day old rat, serum Tyr was unaffected by the saline injections, but the Tyr concentration in the brain decreased markedly at the highest saline dose. The concentrations of NE (only at maximum dose) and of DA (independent on the amount of saline injected) were elevated in the brains of saline injected 20-day old rats. The concentrations of Trp and indoles were more affected at day 5 than at day 20: slightly decreased concentration of Trp in the serum but markedly increased concentrations of brain Trp (only at maximum dose), elevated serotonin (5-HT, independent on the amount of saline injected) and 5-hydroxyindoleacetic acid (5-HIAA, at maximum dose) in the brain. If the maximum dose of 40 μl/g body weight was injected to suckling rats repeatedly during the whole suckling period (in 12 h intervals), some effects caused by one single injection of 40 μl/g disappeared (Tyr—depletion in blood or brain, increase in brain NE, DA and Trp), but other additional effects appeared (decreased DA and increased DOPAC, decreased 5-HT and 5-HIAA). The results show that saline injections do cause characteristic, age-dependent alterations of precursor availability as well as of the rate of synthesis and degradation of catecholamine and 5-HT. Repeated treatments have different effects than one single treatment on the precursor availability and the metabolism of monoamines. These alterations must be taken into account if the effects of certain “specific” treatments are compared and discussed in relation to saline “controls”.  相似文献   

14.
Abstract— Rats were injected intracerebrally with labelled tryptamine, 5-hydroxytrypt-amine (5-HT) and norepinephrine (NE). The disappearance of the amines and their metabolites as a function of time was determined. Tryptamine disappeared very rapidly, with a half-life of 5 min in normal animals and of 45 min in rats treated with a monoamine oxidase (MAO) inhibitor. The level of radioactive 5-HT declined in two phases, with half-lives of 45 min and 3 h respectively. The 5-hydroxyindoleacetic acid (5-HIAA) that was formed disappeared with a half-life of approximately 1 h. After inhibition of monoamine oxidase, there was only a single phase of 5-HT disappearance (half-life of 4 h). Reserpine decreased and imipramine increased the amount of 5-HT remaining 4 h after injection. Of the NE injected, 12 per cent was converted to methoxyhydroxyphenylglycol sulphate (MHPGS), which disappeared with a half life of 3 h. Reserpine doubled the amount of methoxyhydroxyphenylglycol sulfate formed, but did not alter its rate of disappearance, its peak concentration occurring about 30 min after injection of NE in both control and reserpine-treated rats.  相似文献   

15.
We investigated the relationship between the concentration of pyridoxal-5′-phosphate (PLP) and biogenic amine in mouse brain. The production of PLP from pyridoxal (PL) by pyridoxal kinase (PLK) was inhibited by the addition of dopamine (DA), norepinephrine (NE) and 5-hydroxytryptamine (5-HT), but not by that of epinephrine and N-acetyl-serotonin. DA and NE were combined with PLP by a non-enzymatic reaction, whereas 5-HT was bound only slightly with PLP. The conjugated product of PLP with DA was also detected by HPLC analysis when PLK activity was assayed using PL as a substrate in the presence of DA. In an in vivo investigation, the depletion of DA and 5-HT in mouse brain after an intraperitoneal injection of 5 mg/kg reserpine, led to slight elevation of the PLP level to 120% of the control level. By contrast, the increase in DA in the brain caused by intraperitoneal administration of 150 mg/kg L-DOPA caused the PLP concentration to decrease to 70% of the control level. However, no change in PLK activity in the brain was observed when the mice were treated with either reserpine or L-DOPA. These results suggested that the level of PLP in mouse brain was partly regulated by the concentration of biogenic amines, such as DA, NE and 5-HT, without apparent induction of PLK.  相似文献   

16.
Hypothalamic and brainstem biogenic amine metabolism was investigated in rats following the administration of hypothermic doses of 1-Δ9-tetrahydrocannabinol (THC). The dose-dependent fall in body temperature induced by THC was both rapid in onset and prolonged in duration. The disruption in thermoregulation, however, was unaccompanied by any observed alteration in the concentration of turnover rate of 5-hydroxytryptamine (5-HT) in the brain tissues studied. Norepinephrine (NE) was also unchanged, with the exception of a reduction in the amount of brainstem NE 30 min after the administration of 50 mg/kg THC. These observations indicate that the hypothermic effect of THC is not mediated by changes in brain 5-HT or NE metabolism.  相似文献   

17.
This study investigated: (a) the effects of acute 17alpha-methyltestosterone (MT) or 17beta-estradiol (E(2)) administration on norepinephrine (NE), dopamine (DA), serotonin (5-HT), 3,4, dihydroxyphenylacetic acid (DOPAC), and 5-hydroxyindoleacetic acid (5-HIAA) contents in the hypothalamus, telencephalon and pituitary of previtellogenic female rainbow trout Oncorhynchus mykiss, and (b) the effects of chronic MT administration on the levels of these neurotransmitters in these brain regions in immature male rainbow trout. The acute administration of MT induced a significant decrease in pituitary levels of DOPAC as well as in the DOPAC/DA ratio. On the other hand, the acute administration of E(2) induced an increase in pituitary 5-HT levels as well as a decrease in the 5-HIAA/5-HT ratio. In a second experiment, 20 mg MT per kilogram body weight was implanted for 10, 20 or 40 days into sexually immature male rainbow trout. Implanted rainbow trout showed increased testosterone and decreased E(2) levels. In the pituitary, MT induced long-term decreases in NE, DA, DOPAC and 5-HT levels, as well as in the DOPAC/DA ratio. Hypothalamic and telencephalic DA, NE and 5-HT levels were not affected by MT implantation. However, 5-HIAA levels and the 5-HIAA/5-HT ratio were reduced by MT implantation in both brain regions. These results show that chronic treatment with MT exerts both long-term and region-specific effects on NE, DA, and 5-HT contents and metabolism, and thus that this androgen could inhibit pituitary catecholamine and 5-HT synthesis. A possible role for testosterone in the control of pituitary dopaminergic activity and gonadotropin II release is also discussed.  相似文献   

18.
6R-L-Erythro-tetrahydrobiopterin (6R-BH4), the natural isomer of tetrahydrobiopterin, was synthesized from 7,8-dihydrobiopterin using dihydrofolate reductase. The effects of intracerebroventricular injection of 6R-BH4 on the biosyntheses of neurotransmitter monoamines in the rat brain were investigated by measuring accumulation of 3,4-dihydroxyphenylalanine (DOPA) and 5-hydroxytryptophan (5-HTP) after the inhibition of aromatic L-amino acid decarboxylase by NSD 1015 and the contents of metabolites of dopamine (DA) and 5-hydroxytryptamine (5-HT). The formation of DOPA and 5-HTP increased after the injection, reached a maximum level at about 1 h, then leveled off and reached a plateau over 2 h up to 8 h. The formation of DOPA and 5-HTP increased dose-dependently in the whole brain after the injection of 6R-BH4, and reached a plateau when the dose was more than 300 micrograms/rat. The enhancement was 100 and 70% for DOPA and 5-HTP, respectively. The formation of DOPA and 5-HTP increased in four brain regions, but the degree of stimulation was different among the brain regions. The contents of DA and 5-HT metabolites increased after the injection of 6R-BH4 in all brain regions tested, especially in the diencephalon and brain stem. The contents of DA and 5-HT increased slightly after the injection of 6R-BH4. These results suggest that 6R-BH4 concentration may be submaximal within DA and 5-HT neurons, and that an increase in 6R-BH4 in the brain enhances the biosyntheses of DA and 5-HT.  相似文献   

19.
The uptake of 3H-labelled 5-hydroxytryptamine (5-HT, serotonin) norepinephrine ([3H]NE), and 3,4-dihydroxyphenylethylamine ([ 3H]dopamine, [3H]DA) was studied in primary astrocyte cultures prepared from the cerebral cortex, corpus striatum, and hippocampal regions of neonatal rat brain. Na+-dependent uptake showed marked regional differences. For [3H]5-HT the magnitude of uptake was corpus striatum greater than or equal to cerebral cortex greater than hippocampus, whereas for [3H]NE the order was hippocampus greater than corpus striatum greater than cerebral cortex. For [3H]DA, only the hippocampal cultures showed significant Na+-dependent uptake. [3H]5-HT uptake was specifically inhibited by 10(-7) M fluoxetine whereas [3H]NE uptake was preferentially inhibited by 10(-7) M desipramine. These results may reflect regional brain specialization and/or different developmental patterns of high affinity uptake of serotonin and catecholamines by astrocytes in situ.  相似文献   

20.
A procedure is described for the rapid determination of the major indoles and catechols. Analysis with picogram detection limits was done by high-pressure liquid chromatography on a C18 reverse-phase column using electrochemical detection (LCEC). This method provides a comprehensive list of compounds which can be simultaneously determined in brain samples and for which there is no necessity of derivatization or pre-column purification. The regional distribution of 9 neurochemicals from rat brain and the levels of 10 neurochemicals from human brain are presented. DOPA, TYR, NE, MHPG, DOPAC, 5-HIAA, TRP, DA, HVA, 3-MT and 5-HT were detected in the caudate nucleus and putamen. The levels of neurochemicals from the caudate and putamen of a demented patient with Parkinson's disease were variably decreased; catechol and indole losses were greatest in the putamen. The levels of neurochemicals in the caudate and putamen of patients with Alzheimer's disease (SDAT) were also variably decreased; loss of NE was seen only in putamen and losses of DA, HVA and 5-HT were uniform across both caudate and putamen. The CSF of SDAT patients showed changes in NE only.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号