实验性甲状腺功能低下大鼠脑组织单胺类神经递质的代谢变化

采用０．５％ＮａＣｌＯ４诱导实验大鼠甲状腺低功。结果表明，甲低大鼠脑组织去甲肾上腺素（ＮＥ）、５－羟色胺（５－ＨＴ）、５－羟吲哚乙酸（５－ＨＩＡＡ）含量及单胺氧化酶（ＭＡＯ）活性明显高于对照组，且ＮＥ、５－ＨＩＡＡ的改变与ＭＡＯ活性的变化呈正相关，提示：甲低状态下，大脑单胺类神经递质代谢活跃，而ＭＡＯ活性的升高反映了ＭＡＯ在降解单胺类递质，维持大脑功能上起重要作用。补碘实验组大鼠的各项生化指标与对     

硒和维生素E对大鼠心肌腺苷酸及氧化损伤的影响

目的：研究低硒（Ｓｅ）低维生素Ｅ（ＶＥ）饮食大鼠心肌腺苷酸含量和氧化损伤的关系。方法：使用高效液相测定心肌腺苷酸含量和使用生化方法测定心肌ＭＤＡ含量和ＳＯＤ、ＧＳＨ－Ｐｘ活性。结果：与补充Ｓｅ和／或ＶＥ饮食大鼠相比，低Ｓｅ低ＶＥ饮食大鼠心肌ＡＭＰ，ＡＤＰ含量无明显差异，而ＡＴＰ含量明显降低，ＭＤＡ含量增加，ＳＯＤ，ＧＳＨ－Ｐｘ活性降低，表明Ｓｅ和ＶＥ影响ＡＴＰ含量与其抗氧化作用有关，而其中以联合补充Ｓｅ和ＶＥ效果最佳     

氟对大鼠子代脑单胺类神经介质的影响

Ｗｉｓｔａｒ大鼠自查到阴栓起，分别自由饮用０．６ｍｇ／Ｌ（对照组）、１ｍｇ／Ｌ、５ｍｇ／Ｌ、２５ｍｇ／Ｌ含氟水，其仔鼠饮用同浓度含氟水至９０ｄ，观察胚胎期及生长发育期接触氟对仔鼠大脑功能的影响。采用高压液相色谱－电化学法对大脑单胺类神经介质测定结果显示，除多巴胺的代谢产物之一－３，４－二羟乙酸（ＤＯＰＡＣ）的含量在高剂量组显著降低外，去甲肾上腺素（ＮＥ）、多巴胺（ＤＡ）、高香草酸（ＨＶＡ）、５－羟色胺（５－ＨＴ）和５－羟吲哚乙酸（５－ＨＩＡＡ）的含量与对照组比较均无显著差异，表明氟可抑制ＤＡ的代谢转化，对单胺氧化酶（ＭＡＯ）的活性有一定的抑制作用。提示氟对仔鼠的大脑功能有一定的不良影响。     

硒和维生素E对冷刺激条件下心肌内皮素和心肌营养性血流量的影响

低硒（Ｓｅ）低维生素Ｅ（ＶＥ）饲料喂养大鼠和小鼠１０周，处死前均经两次冰浴刺激。小鼠静脉注射８６Ｒｂ，测定心肌放射性计数，以此代表心肌营养性血流量；取大鼠心肌经放免测定内皮素（ＥＴ）含量。结果显示：低Ｓｅ低ＶＥ饮食小鼠心肌营养性血流量明显降低，同样饮食大鼠心肌ＥＴ含量明显增加，通过补充Ｓｅ和ＶＥ，可使心肌营养性血流量和心肌ＥＴ水平有不同程度的改善，这些结果有助于深入探讨克山病心肌坏死的发生机制。     

钙硒与维生素E对饲予克山病病区粮大鼠心肌细胞抗氧化能力…

用克山病病区粮组成偏食低钙基础饲料及在饲料中补一定剂量钙、硒与维生素Ｅ（ＶＥ），观察其对大鼠心肌细胞抗氧化酶系活性及在一过性缺氧条件下心肌酶活性的影响。结果表明病区粮组成的偏食低钙饲料引起大鼠心肌组织ＧＳＨ－Ｐｘ，ＳＯＤ及Ｃａｔ活性明显降低，ＬＰＯ含量升高。在ＮａＮＯ２引起的缺氧条件下，心肌多种酶活性下降，而血清酶活性升高。联合补充钙，硒与ＶＥ可显著提高心肌细胞抗氧化酶系活性及增强心肌细胞抵抗缺氧     

硒和维生素E对冷应激条件下大鼠心肌NO和血浆PAR的影响

①目的：研究克山病病区粮（ＥＧ）饮食大鼠在冷应激条件下，引起心肌缺血的相关因素。②方法：用比色法测定心肌匀浆中一氧化氮（ＮＯ）和氧化氮合成酶（ＮＯＳ），并测定血浆血小板聚集率（ＰＡＲ）、凝血酶原时间（ＰＴ）和白陶土部分凝血活酶时间（ＫＰＴＴ）。③结果：ＥＧ饮食大鼠心肌ＮＯ含量和ＮＯＳ活性降低；ＰＡＲ明显增高、ＰＴ无明显改变，但（ＫＰＴＴ）明显延长，补充Ｓｅ和／或ＶＥ可有不同的改善作用。④结论：ＥＧ     

不同水平维生素B2和A对热应激产生脂质过氧化的影响

目的研究摄入不同水平维生素Ｂ２（ＶＢ２）和维生素Ａ（ＶＡ）对受热应激机体内脂质过氧化的影响。方法５组大鼠分别喂以正常、缺乏或补充不同剂量ＶＢ２和ＶＡ的饲料，４ｗ后，在干球温度３９℃，相对湿度７０％下应激６０ｍｉｎ，立即测其血液、肝、肾、股四头肌中超氧化物歧化酶（ＳＯＤ）活性和丙二醛（ＭＤＡ）含量。结果缺乏ＶＢ２和ＶＡ使组织ＳＯＤ活性显著降低，ＭＤＡ含量显著升高，而补充ＶＢ２和ＶＡ使组织ＳＯＤ活性显著升高。ＭＤＡ含量显著降低；二种维生素表现出协同效应。结论补充ＶＢ２和ＶＡ可以降低热应激对机体造成的脂质过氧化损伤     

硒,维生素E对心肌内Ang—II含量影响及其与胶原代谢关系的…

用低硒（Ｓｅ）低维生素Ｅ（ＶＥ）饲料喂养大鼠６０ｄ后。实验组射异丙肾上腺素（ＩＳＰ）使心肌发生坏死。检测坏死后心肌组织中血管紧张素Ⅱ（Ａｎｇ－Ⅱ）和血管紧张素Ｉ转换酶（ＡＣＥ）活性，同时测定组织内胶原蛋白含量变化。结果发现低Ｓｅ、ＶＥ饮食大鼠组织内Ａｎｇ－Ⅱ水平升高，ＡＣＥ活性也升高，组织内胶原蛋白含量增加，补Ｓｅ、ＶＥ后上述改变减轻。这些结果提示，低Ｓｅ、ＶＥ饮食降低了心肌细胞对损伤的耐受性，心     

硒锰锌维生素E与心肌损伤关系的实验研究

用低Ｓｅ高Ｍｎ人工半合成饲料喂饲大白鼠，复制动物心肌损伤模型。补加Ｓｅ（０．３ｍｇ／ｋｇ）、Ｚｎ（２００ｍｇ／ｋｇ）、ＶＥ（２００ＩＵ／ｋｇ）．以观察单纯补加Ｓｅ、Ｚｎ、ＶＥ或三者不同组合对心肌损伤的影响。实验结果表明，单纯补加因素中，补加ＶＥ组大鼠的心肌坏死检出率与低Ｓｅ高Ｍｎ组比下降（Ｐ＜０．０５），坏死面积也缩小，心肌ＳＤＨ和ＣＣＯ活性提高。补加二因素组中．补加Ｓｅ＋Ｚｎ和Ｓｅ＋ＶＥ组大鼠心肌坏死检出率下降（Ｐ＜０．０５），而补加Ｓｅ十ＶＥ组下降更明显，心肌ＳＤＨ和ＣＣＯ活性提高更明显。补加Ｓｅ＋Ｚｎ＋ＶＥ组大鼠心肌坏死检出率进一步降低（Ｐ＜０．０５），坏死面积也最小，心肌ＣＣＯ活性明显提高．ＳＤＨ活性改变不明显。     

硒和维生素E对冷刺激条件下心肌内皮素和心肌营养性血流量…

低硒（Ｓｅ）低维生素Ｅ（ＶＥ）饲料喂养大鼠和小鼠１０周，处死前均经两次冰浴刺激。小鼠静脉注射＾８６Ｒｂ，测定心肌放射性计数，以此代表心肌营养性血流量；取大量心肌经放免测定内皮素（ＥＴ）含量。结果表明：低Ｓｅ低ＶＥ饮食小鼠心肌营养性血流量明显降低，同样饮食大鼠心肌ＥＴ含量明显增加，通过补充Ｓｅ和ＶＥ，可使心肌营养性血流量和心肌ＥＴ水平有不同程度的改善，这些结果有助于深入探讨克山病心肌坏死的发生机制。     

硒与维生素E的协同影响对心肌损伤保护的研究

通过在低硒富锰饲料中联合补充硒及ＶＥ喂养大鼠，并以亚硝酸钠作为诱发因素建立大鼠心肌损伤模型，观察硒与ＶＥ的协同作用对心肌损伤的保护效果。结果表明，在低硒环境下，富锰能显著提高心肌坏死检出率及降低机体抗氧化能力。单纯补充硒及ＶＥ均可对抗富锰的影响，但硒与ＶＥ的联合补充效果更佳。     

敦煌石室大宝胶囊对衰老大鼠脑组织单胺类神经递质的影响

目的 观察敦煌石室大宝胶囊(DHDB)对衰老模型大鼠脑组织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)含量的影响.方法 采用D-半乳糖建立大鼠衰老模型,测定大脑皮层内的NE、DA和5-HT含量.结果 模型组大鼠脑组织内NE、DA、5-HT含量与空白组比较均有明显降低(P<0.05),应用DHDB治疗后,治疗组大鼠脑组织内NE、DA、5-HT含量均显著增高(P<0.05).结论 DHDB可提高衰老模型动物脑组织单胺类神经递质的含量,对改善大脑功能有一定的作用.     

硒、维生素E、锌与低硒、富锰引起大鼠心肌损伤的关系

目的探讨硒、维生素E(VE)、锌单因素及复合因素对低硒、富锰心肌损伤的影响。方法用低硒、富锰人工半合成饲料喂饲大白鼠8周。补充硒(0．3mg／kg)或VE(250mg／kg)或锌(200mg／kg)。结果单因素硒、VE、锌及复合因素均可使血清谷胱甘肽过氧化物酶(GSH—Px)活性提高，使心肌组织脂质过氧化物(LPO)值明显降低，心肌坏死检出率有降低的趋势。结论复合因素好于单因素，3因素明显好于双因素。     

低硒环境下蛋氨酸对大鼠体内维生素E,硒及脂质过氧化物含量的影响

用低硒、低蛋氨酸饲料喂养大鼠8周后发现大鼠血清、肝脏及心肌中脂质过氧化物含量显著升高,血清维生素E显著下降,而心肌硒含量却显著升高。实验结果表明,在低硒环境下如降低饲料中蛋氨酸水平将导致大鼠体内脂质过氧化反应加剧。     

Aging and diurnal rhythms of pineal serotonin, 5-hydroxyindoleacetic acid, norepinephrine, dopamine and serum melatonin in the male rat

Pineal serotonin (5-HT), 5-hydroxyindoleacetic acid (5-HIAA), norepinephrine (NE) and dopamine (DA) were measured by high-pressure liquid chromatography with electrochemical detection and serum melatonin was measured by radioimmunoassay in rats aged 3 weeks, 8 weeks and 18 months. They were killed either at mid-light or mid-dark of a 12 h light:12 h dark cycle. Diurnal rhythms were observed for 5-HT and 5-HIAA in all ages studied while those for NE and DA were not observed in the 18-month-old animals. Pineal 5-HT and 5-HIAA were higher in 3-week-old rats at mid-dark, and lower at mid-light than in older animals. The pineal content of NE was lower in the 3-week-old rats at mid-dark and mid-light compared with that in the 8-week-old while the DA content was lower at mid-dark. In addition, pineal 5-HT, 5-HIAA, NE and DA were lower in the 18-month-old than in the 8-week-old animals at mid-dark. At mid-dark serum melatonin levels showed an age-related decrease. This study shows that an age-related decrease of pineal 5-HT, 5-HIAA, NE and DA can only be demonstrated at mid-dark and that the age-related decrease of melatonin may not be due to a decrease in sympathetic activity.     

克山病病区粮喂饲大鼠组织维生素E和Se GSH—Px的测定分析

用克山病病区粮喂饲大鼠15周,其肝脏、心脏、胰腺、肾脏、脾脏及全血Se GSH-Px活性都明显低于非病区粮喂养的大鼠,骨骼肌Se GSH-Px活性亦有降低的趋势,但差异不显著。Vit.E测定的结果表明,用病区粮喂养的大鼠肝脏和血清中Vit.E的含量明显高于用非病区粮喂养的大鼠;肾脏、脾脏和胰腺中Vit.E的含量和非病区粮组大鼠相比,亦有增高的趋势,但没有统计学差异;唯独在心肌和骨骼肌中Vit.E的含量两组间基本相同,病区粮组无丝毫增多迹象。 病区粮喂养大鼠肝脏和血清中Vit.E含量明显增多是吸收增多的表现,是对体内低硒的代偿反应,说明病区粮喂养大鼠体内对Vit.E的需要量增加。Vit.E在体内变化不一致,说明各脏器对Vit.E的摄取能力存在着差异,由于心肌和骨骼肌摄入Vit.E的能力较弱,尤易发生Vit.E相对不足的现象,成为克山病病变之主要靶器官。因此应重视硒和Vit.E联合缺乏在克山病发病中的作用。     

Effects of dietary selenium and vitamin E on plasma lipoprotein cholesterol levels in male rats

Male Fischer-344 rats fed a diet deficient in both vitamin E and selenium (Se) for 20 weeks had higher levels of low-density lipoprotein cholesterol than age-matched rats fed an identical diet but supplemented with these micronutrients. The rats supplemented with both vitamin E and Se were switched to a diet deficient in both these micronutrients at week 20. These rats eventually developed elevated levels of low-density lipoprotein cholesterol compared to age-matched rats either continuously maintained on the diet supplemented with vitamin E and Se or rats switched (at week 20) from the vitamin E-and Se-deficient diet to a diet supplemented with both these micronutrients. In a second experiment, we found that Se deficiency alone was sufficient to significantly elevate low-density lipoprotein cholesterol. The basal diet used in these experiments had a very low cholesterol content and the observed alterations in lipoprotein cholesterol levels are likely to reflect alterations in the metabolism of endogenously synthesized cholesterol.     

Maturation of the prolactin and proopiomelanocortin-derived peptide responses to ether stress and morphine: neurochemical analysis

The hormonal and neurochemical responses to acute ether stress, morphine, and/or naloxone were analyzed in infantile (13-day-old) and prepubertal (36-day-old) male CD rats in an attempt to identify a possible neurochemical correlate(s) for the previously demonstrated requisite maturation of the PRL response to ether stress. Neuronal serotonin (5-HT), norepinephrine (NE), and dopamine (DA) activities were examined in the medial preoptic hypothalamic area (MPOH), medial basal hypothalamic area (MBH), and median eminence (ME). Ether stress increased plasma PRL, ACTH, and beta-endorphin-like immunoreactivity (beta end) as well as NE metabolism in the MPOH and MBH and neuronal 5-HT activity in the MBH, and decreased neuronal DA activity in the ME of prepubertal animals. Ether stress elicited similar changes in infantile animals, with the important exceptions that plasma PRL, neuronal 5-HT activity in the MBH, and neuronal DA synthesis in the ME were not affected at this earlier age. Morphine increased plasma PRL, ACTH, and beta end levels, elevated neuronal NE and 5-HT activities in the MPOH and MBH, and decreased DA synthesis in the ME in both infantile and prepubertal animals. Naloxone administration did not alter basal hormone concentrations or neuronal monoamine activity in any brain area, but did prevent all of the morphine-induced changes as well as the ether stress-induced changes in PRL, MBH neuronal 5-HT activity, and DA synthesis in the ME of prepubertal animals. In addition, naloxone augmented the ether stress-induced increases in ACTH and beta end in prepubertal rats. Indirect stimulation of 5-HT neurons by administration of the amino acid precursor of 5-HT, 5-hydroxytryptophan, resulted in decreased DA synthesis in the ME of infantile animals and increased plasma PRL levels in that age group, indicating that this portion of the neurochemical connection is already present in infantile animals. Furthermore, the 5-hydroxytryptophan-induced increase in PRL was blocked by pretreatment with naloxone. The results demonstrate that both the ether stress- and morphine-induced increases in plasma PRL, but not in ACTH or beta end, are associated with increased neuronal 5-HT activity in the MBH and a decreased neuronal DA activity in the ME, that these are opiate receptor-mediated effects, and that infantile rats apparently lack a functional opiate-5-HT connection, which matures some time between days 13 and 36 postnatally.