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31.
We have tested the hypothesis that DNA markers in the MAOA gene show allelic association with bipolar affective disorder. Eighty-four unrelated Caucasian patients with DSM III-R bipolar disorder and 84 Caucasian controls were typed for three markers in MAOA: a dinucleotide repeat in intron 2, a VNTR in intron 1, and an Fnu4HI RFLP in exon 8. No evidence for allelic association was observed between any of the markers and bipolar disorder. © 1995 Wiley-Liss, Inc.  相似文献   
32.
33.
Platelet monoamine oxidase activity in Down's syndrome   总被引:1,自引:0,他引:1  
The activity of platelet monoamine oxidase in Down's syndrome cases was significantly lower than that of controls. This difference was found for both males and females, and with tyramine, tryptamine and β-phenethylamine as substrate. The Km values of the monoamine oxidase towards tryptamine as substrate from controls and Down's syndrome patients were similar.  相似文献   
34.
本文用组织化学方法,选择能反映神经组织糖代谢三个途径的关键酸及碱性磷酸酶,对正常SD系大鼠海马酶活性进行半定量研究.结果CA1区锥体层琥珀酸脱氢酶(SDH)及细胞色素氧化酶(CCO)呈轻度反应,葡萄糖-6一磷酸脱氢酶(G—6—PD)及乳酸脱氢酶(LDH)呈强阳性.腔隙分子层LDH、G—6—PD呈轻度活性,CCO、SDH呈强阳性.CA1区锥体层碱性磷酸酶(AKP)活性最弱.讨论了酶活性不同与记忆的关系及临床意义.  相似文献   
35.
Summary Injections of horseradish peroxidase conjugated with wheat germ agglutinin (WGA-HRP) were made into the cortex of kittens. When cytochrome oxidase histochemistry was performed on sections taken through the injection sites staining of the WGA-HRP deposits occurred, demonstrating that WGA-HRP can cross-react during processing for cytochrome oxidase.  相似文献   
36.
T cell lymphopenia in the peripheral blood lymphocytes (PBL) of patients with AT is mainly caused by a decrease of naive CD45RA+/CD4+ cells followed by a predominance of memory CD45RO+ lymphocytes. To relate these findings to the regulation of programmed cell death, we investigated the activation state and apoptotic level of PBL in 12 patients and healthy controls by flow cytometry. In accordance with previous investigations, the number of naive CD4+/CD45RA+ cells was significantly decreased in patients compared with healthy controls. This disturbed balance of CD45RA and CD45RO was also reflected in higher amounts of activated HLA-DR and CD95 expressing cells, with a concomitant decrease of Bcl-2 protected lymphocytes in the T cell population. With regard to its role in preventing oxidative-induced cell death, we analysed Bcl-2 expression and apoptosis in the presence of oxidative stress. In culture, cells of patients are more susceptible to spontaneous programmed cell death. However, in our stress-inducing system (hypoxanthine/xanthine oxidase system) the number of cells undergoing apoptosis was lower in patients' cell populations compared with controls. In addition, preliminary results suggest that Bcl-2 expression and level of spontaneous apoptosis in patients can be modified by IL-2 and interferon-gamma.  相似文献   
37.
Summary Equol, its methylated derivative, and a carbazole, all isolated from bovine urine, are relatively potent inhibitors of monoamine oxidase with IC50 values of 158, 28, and 16M respectively (using 83M tyramine as substrate). The probable dietary origin of these compounds suggests that natural monoamine oxidase inhibitors may be more widespread than had previously been suspected.  相似文献   
38.
Summary The 5-hydroxytryptamine (5HT) receptor agonist, 5-methoxytryptamine, inhibited in a concentration-dependent manner the electrically-evoked release of 3H-5HT from superfused rat hypothalamic slices, with an IC50 of 560 nmol/l, without affecting the spontaneous outflow of radioactivity. In the presence of the selective monoamine oxidase B (MAO B) inhibitor, (–)-deprenyl (1 mol/l), the concentration-effect curve for 5-methoxytryptamine was shifted significantly to the left, and the IC50 was decreased to 25 nmol/l. Under the same experimental conditions, the potency of the 5HT receptor agonist lysergic acid diethylamide (LSD) at inhibiting the electrically-evoked release of 3H-5HT was the same in the presence as well as in the absence of (–)-deprenyl. The IC50 values for LSD were 34 nmol/l in the absence of deprenyl, and 31 nmol/l in the presence of the MAO B inhibitor. It is concluded that deprenyl potentiates the inhibition by 5-methoxytryptamine of 3H-5HT release, by preventing its inactivation through MAO B. Since 5-methoxytryptamine may be present in the pineal gland of some species, the potent effects of this 5-HT receptor agonist on seretoninergic neutrotransmission may be of physiological relevance.  相似文献   
39.
Summary The in vitro inhibition by amiflamine [FLA 336(+)] and related compounds of the activity of rat monoamine oxidase (MAO)-A and-B, rat semicarbazide sensitive amine oxidase (SSAO) and human platelet poor plasma benzylamine oxidase was studied. Amiflamine was an MAO-A selective inhibitor, but also inhibits SSAO with both a reversible (competitive, K i=200 mol/l) and a small time-dependent component which was irreversible in nature. The optical isomer FLA 336(–) was ten times less potent towards MAO-A. However, this compound was much more potent an inhibitor of SSAO (competitive, K i=4.6 mol/l). The amiflamine metabolites FLA 788(+) and FLA 668(+) inhibited SSAO, but only at concentrations considerably higher than required for MAO-A inhibition. Ex vivo experiments indicated that there was no significant irreversible inhibition of rat heart and lung SSAO after both single and repeated administration of amiflamine at doses up to 20 times higher than required for inhibition of MAO-A within central serotoninergic neurones.  相似文献   
40.
为研究益元活血丹和大黄及血栓心脉宁对老龄大鼠脑缺血再灌注心肌损伤防护作用的机制。将老龄大鼠分为对照组、模型组、尼莫地平组、益元活血丹大小剂量组、大黄组、血栓心脉宁组,观察LDH、CPK活性和NE、DA、E、ET、CGRP、NPY的含量的变化。模型组血清中CPK、LDH活性和血浆ET及脑组织NPY含量增高,交感-肾上腺系统兴奋增强。与模型组比较,大黄组血清LDH和CPK活性减低,益元活血丹大剂量组和血栓心脉宁组及大黄组血浆ET含量、大黄组和益元活血丹大剂量组脑组织NPY含量降低,益元活血丹小剂量组血浆中CGRP水平增高;用药各组交感-肾上腺系统兴奋减低。提示大黄和血栓心脉宁及益元活血丹对心肌损伤的保护作用可能与其抑制交感-肾上腺系统兴奋增强和调节CGRP与ET间的平衡失调有关。  相似文献   
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