一种大鼠动脉粥样硬化斑块模型的建立

目的试建立一种大鼠动脉粥样硬化斑块模型。方法给予大鼠一次维生素D33×105U/kg体重肌肉注射、球囊损伤主动脉内皮和饲以含2％胆固醇、0.5％胆酸钠、0.2％丙硫氧嘧啶、3％猪油和维生素D31.25×106U/kg的高脂饲料90 d。结果90 d后大鼠血脂明显增高,胸主动脉形成明显的动脉粥样硬化斑块,斑块内有大量的泡沫细胞、脂质、巨噬细胞及钙化,中膜平滑肌明显萎缩;而仅饲以高脂饲料的大鼠胸主动脉结构未见改变。结论血管钙超载、内皮损伤和高脂可使大鼠主动脉形成较典型的动脉粥样硬化斑块。     

三种剂量维生素D3结合高脂饲料建立大鼠动脉粥样硬化模型的比较

目的 探讨维生素D3结合高脂饲料建立大鼠动脉粥样硬化模型的方法.方法 健康雄性Wistar大鼠40只随机平均分为四组:对照组、模型1组、模型2组、模型3组.对照组喂常规饲料,模型组喂高脂饲料.模型1组在造模前腹腔注射维生素D370万IU/kg,分4次每隔两天注射;模型2组在造模前注射60万IU/kg,造模后第3、6、9周分别注射10万IU/kg;模型3组在造模前和造模后第3、6、9周分别注射60万IU/kg;喂养12周后比较各组动物体重、血脂和主动脉病理变化.结果 12周后,模型组各组体重较对照组明显下降(P＜0.01),其中模型3组体重下降最显著且死亡率最高;模型组各组的血清总胆固醇和低密度脂蛋白胆固醇与对照组比较均明显升高(P＜0.01);模型1、2、3组造模成功只数分别为3只、8只和5只.结论 高脂饲料结合造模前腹腔注射维生素D360万IU/kg,造模后第3、6、9周各补充10万IU/kg是比较有效的制备动脉粥样硬化大鼠模型方法.     

普萘洛尔对大鼠动脉粥样硬化斑块内MMP-9及TIMP-1表达的影响

目的探讨普萘洛尔对大鼠动脉粥样硬化斑块内基质金属蛋白酶-9(MMP-9)及金属蛋白酶组织抑制剂-1(TIMP-1)表达的影响。方法30只Wistar大鼠经高脂、高维生素D、免疫损伤处理17周造成动脉粥样硬化模型,随机分为对照组和普萘洛尔组,每组15只。所有大鼠在继续高脂喂养基础上,普萘洛组予普萘洛尔5mg/(kg.d)灌胃;对照组予生理盐水1ml/d灌胃,一周后处死全部大鼠,取主动脉粥样硬化斑块用免疫组织化学方法检测动脉粥样硬化斑块内巨噬细胞浸润、MMP-9及TIMP-1表达。结果普萘洛尔组巨噬细胞浸润数目及MMP-9的表达较对照组明显减少(P0.01),TIMP-1表达明显增高(P0.05)。结论普萘洛尔减少大鼠动脉粥样硬化斑块处巨噬细胞浸润及MMP-9表达,增加TIMP-1表达,具有稳定动脉粥样硬化斑块作用。     

三种大鼠动脉粥样硬化模型复制方法的比较

为研究动脉粥样硬化的发病机制,比较了三种大鼠动脉粥样硬化斑块模型建立的方法.分别予单纯高脂、高脂+维生素D、高脂+维生素D+内皮损伤三种不同方法处理大鼠,90天后比较血脂、血钙、胸主动脉的形态学改变、巨噬细胞和α-平滑肌肌动蛋白含量.结果发现,三组实验组与正常对照组相比,总胆固醇、甘油三酯和低密度脂蛋白胆固醇均明显升高(P<0.01);高脂+维生素D组、高脂+维生素D+内皮损伤组与正常对照组和高脂组相比,血钙均明显升高(P<0.01);高脂+维生素D组、高脂+维生素D+内皮损伤与正常对照组相比,内膜增厚、中膜萎缩(P<0.05或P<0.01);单纯高脂组、高脂+维生素D组CD68为弱阳性,高脂+维生素D+内皮损伤组为强阳性;高脂+维生素D组内膜有较厚的α-平滑肌肌动蛋白阳性,高脂+维生素D+内皮损伤组斑块表面只有很薄的α-平滑肌肌动蛋白阳性;单纯高脂组只可形成高脂血症,无法形成动脉粥样硬化病变;高脂+维生素D组可形成纤维斑块;高脂+维生素D+内皮损伤组可形成较成熟的动脉粥样硬化斑块.证明了大鼠可作为研究动脉粥样硬化的良好动物模型,高脂+维生素D+内皮损伤组可形成较成熟的动脉粥样硬化斑块.     

稳消Ⅱ方对兔腹主动脉粥样硬化模型NF-κB P65蛋白表达的影响

目的观察稳消Ⅱ方对兔动脉粥样硬化模型腹主动脉壁核因子-κB(NF-κB)P65蛋白表达的影响,探讨其抗动脉粥样硬化的作用机制。方法将38只健康新西兰大白兔随机分为空白组(9只)和造模组(29只),分别给予标准饲料和高脂饲料。8周后,造模组随机处死1只兔子,确认造模成功。将造模组随机分为3组:稳消Ⅱ方组、辛伐他汀组、模型对照组,停用高脂饲料,改用标准饲料,分别给予稳消Ⅱ方、辛伐他汀、蒸馏水灌胃治疗8周,处死动物,采用免疫组化法观察NF-κB P65表达。结果与模型对照组比较,稳消Ⅱ方组和辛伐他汀组NF-κBP65表达均显著下降,差异有统计学意义(P0.05);干预前后稳消Ⅱ方组和辛伐他汀组同组比较,差异有统计学意义(P0.05)。结论稳消Ⅱ方可能通过抑制NF-κB P65表达防治和稳定动脉粥样硬化斑块,减少心脑血管病不良事件的发生。     

主动脉中膜钙化型动脉粥样硬化模型的建立

目的探讨SD大鼠在维生素D3联合高脂饲料处理下,90 d建立动脉粥样硬化(AS)模型的可行性。方法雄性SD大鼠60只,随机分成:对照组和AS组。对照组予以基础饲料饲养,AS组维生素D3以60万U/kg实验开始前4 d连续腹腔注射,之后以30万U·kg-1·30 d-1的剂量腹腔注射,并联合高脂饲料饲养90 d。检测0、45及90 d血清总胆固醇(TC)、钙离子和高密度脂蛋白胆固醇(HDL-C)浓度。HE染色法检测AS过程中主动脉动态病理变化。结果 90 d AS组TC、动脉粥样硬化指数(AI)及钙离子浓度显著高于0 d和90 d对照组(均P<0.05),90 d时出现主动脉中膜钙化型AS斑块。结论 SD大鼠在维生素D3联合高脂饲料处理下,90 d成功构建了主动脉中膜钙化型AS模型。     

普萘洛尔对大鼠动脉粥样硬化斑块内基质金属蛋白酶-9(MMP-9)及金属蛋白酶组织抑制剂-1(TIMP-1)表达的影响

目的 研究普萘洛尔对大鼠动脉粥样硬化斑块内基质金属蛋白酶-9(MMP-9)及金属蛋白酶组织抑制剂-1(TIMP-1)表达的影响,探讨β-受体阻滞剂稳定动脉粥样硬化斑块的机制.方法 30只Wistar大鼠经高脂、高维生素D、免疫损伤处理17 w造成动脉粥样硬化模型后,随机分为对照组和普萘洛尔组,每组15只.所有大鼠在继续高脂喂养基础上,普萘洛组予普萘洛尔5 mg·kg-1·d-1灌胃;对照组予生理盐水1 ml/d灌胃.分组处理1 w后处死全部大鼠,取主动脉粥样斑块用免疫组织化学方法检测动脉粥样硬化斑块内CD68巨噬细胞浸润、MMP-9及TIMP-1表达.结果 普萘洛尔组巨噬细胞浸润数目及MMP-9的表达较对照组明显减少(P<0.01),TIMP1表达明显增高(P<0.05).结论 普萘洛尔可减少大鼠动脉粥样硬化斑块处巨噬细胞浸润及MMP-9的表达,增高斑块处TIMP-1表达,具有稳定动脉粥样硬化斑块的作用.     

建立实验性大鼠不稳定粥样斑块模型的可行方法

目的 探索一种建立实验性大鼠不稳定粥样斑块模型的可行方法.方法 40只雄性Wistar大鼠随机分为对照组（C组）、大鼠胸主动脉粥样硬化斑块模型组（A1、A2、A3组）,每组各10只.A1、A2模型组大鼠使用高脂饲料＋维生素D3复合造模,A3组大鼠使用高脂饲料＋维生素D3＋大鼠血管内皮球囊损伤复合造模.A1组大鼠喂食高脂饲料1,A2和A3组大鼠喂食高脂饲料2,C组大鼠喂食普通标准饲料.16周后检测各组大鼠身长、体重及血脂水平,观察胸主动脉病理学变化,流式检测外周血T淋巴细胞的数量.结果 各模型组大鼠血脂总胆固醇（TC）和低密度脂蛋白胆固醇（LDL-C）水平明显高于C组.A1组大鼠因造模过程中食欲严重低下,16周末死亡6只,剩余4只生长发育缓慢,A2、A3组大鼠体型肥胖,C组大鼠生长发育正常.主动脉苏木素-伊红（HE）染色显示,A3组大鼠胸主动脉形成了不稳定粥样斑块,A1、A2组大鼠胸主动脉只观察到动脉壁硬化,C组大鼠呈现正常形态的胸主动脉.C组、A1组和A2组大鼠外周血T淋巴细胞百分含量显著低于A3组大鼠, A1、A2组大鼠外周血T淋巴细胞百分含量较C组大鼠轻微升高,但差异无统计学意义.结论 高脂饲料的配方及大鼠动脉内膜的损伤对建立大鼠不稳定粥样斑块模型有着至关重要的影响.利用特殊的高脂配方饲料加上维生素D和球囊损伤血管内膜,可以建立一种可行的实验性大鼠不稳定粥样斑块模型.     

补阳还五汤对动脉粥样硬化大鼠模型血脂的影响

目的利用高脂饲料加维生素D3诱发的动脉粥样硬化(AS)模型,观察益气活血代表方剂补阳还五汤对AS模型血脂的影响,探讨其治疗作用及可能机制。方法大鼠动脉粥样硬化造模成功后,随机分为4组。补阳还五汤治疗组:造模成功后给予补阳还五汤17.5g/(kg·d)灌胃;川芎嗪治疗组:造模成功后给予川芎嗪0.2g/(kg·d)灌胃;正常对照组一直饲喂普通饲料;模型组造模成功后改喂普通饲料。灌胃30d。用药一月后测定血脂水平。结果高脂饮食加维生素D3可诱导大鼠形成动脉粥样硬化模型,模型组的血脂明显高于正常组。补阳还五汤治疗组的总胆固醇(TC)、三酰甘油(TG)、低密度脂蛋白(LDL)水平均显著低于川芎嗪治疗组、模型组。结论益气活血的代表方剂补阳还五汤具有抗动脉粥样硬化作用,下调血脂水平可能是其作用机制之一。     

沙棘黄酮对大鼠动脉粥样硬化斑块的影响及作用机制

目的 探究沙棘黄酮(TFH)对大鼠动脉粥样硬化(AS)斑块的影响及机制.方法 SPF级、雄性SD大鼠100只,随机分为对照组、模型组、阳性对照组及实验组,每组25只.模型组、阳性对照组及实验组均采用腹腔注射维生素D3,高脂饲料喂养8 w构建AS大鼠模型.造模成功后,阳性对照组给予阿托伐他汀钙10 mg/(kg·d)灌胃...     

Three layer functional model and energy exchange concept of aging process

Relying on a certain degree of abstraction, we can propose that no particular distinction exists between animate or living matter and inanimate matter. While focusing attention on some specifics, the dividing line between the two can be drawn. The most apparent distinction is in the level of structural and functional organization with the dissimilar streams of ‘energy flow’ between the observed entity and the surrounding environment. In essence, living matter is created from inanimate matter which is organized to contain internal intense energy processes and maintain lower intensity energy exchange processes with the environment. Taking internal and external energy processes into account, we contend in this paper that living matter can be referred to as matter of dissipative structure, with this structure assumed to be a common quality of all living creatures and living matter in general. Interruption of internal energy conversion processes and terminating the controlled energy exchange with the environment leads to degeneration of dissipative structure and reduction of the same to inanimate matter, (gas, liquid and/or solid inanimate substances), and ultimately what can be called ‘death.’ This concept of what we call dissipative nature can be extended from living organisms to social groups of animals, to mankind. An analogy based on the organization of matter provides a basis for a functional model of living entities. The models relies on the parallels among the three central structures of any cell (nucleus, cytoplasm and outer membrane) and the human body (central organs, body fluids along with the connective tissues, and external skin integument). This three-part structural organization may be observed almost universally in nature. It can be observed from the atomic structure to the planetary and intergalactic organizations. This similarity is corroborated by the membrane theory applied to living organisms. According to the energy nature of living matter and the proposed functional model, the decreased integrity of a human body's external envelope membrane is a first cause of the structural degradation and aging of the entire organism. The aging process than progresses externally to internally, as in single cell organisms, suggesting that much of the efforts towards the restoration and maintenance of the mechanisms responsible for structural development should be focused accordingly, on the membrane, i.e., the skin. Numerous reports indicate that all parts of the human body, like: bones, blood with blood vessels, muscles, skin, and so on, have some ability for restoration. Therefore, actual revival of not only aging tissue of the human body's membrane, but the entire human body enclosed within, with all internal organs, might be expected. We assess several aging theories within the context of our model and provide suggestions on how to activate the body's own anti-aging mechanisms and increase longevity. This paper presents some analogies and some distinctions that exist between the living dissipative structure matter and inanimate matter, discusses the aging process and proposes certain aging reversal solutions.     

The immunoneuroendocrine role of melatonin

Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.     

Unusual responses of nocturnal pineal melatonin synthesis and secretion to swimming: Attempts to define mechanisms

Abstract: The effect of swimming at night on rat pineal melatonin synthesis was compared with that of light exposure at night. Rats were forced to swim at 0030 hr (lights out at 2000 hr) and sacrificed by decapitation 15 and 30 min later, immediately after swimming. Other groups of animals were exposed to white light (650μW/cm²) for 15 and 30 min at same time. Swimming caused a rapid and highly significant drop in the melatonin content in the pineal gland; however, the activity of N-acetyltransferase (NAT), the supposed rate limiting enzyme in the melatonin production, was not changed. Despite the drop in pineal melatonin levels, serum concentrations of the indole remained elevated in the rats that swam. In contrast, melatonin levels in the pineal and serum of light exposed rats fell precipitously, accompanied by a significant suppression of NAT activity. Since we anticipated that the strenuous exercise associated with swimming may induce release of artrial natriuretic peptide (ANP) from the heart, which in turn could cause the release of pineal melatonin, in a second study we injected physiological saline intravenously to stretch the cardiac muscle and release ANP. Three milliliters of normal saline was injected during the day into the jugular vein of anesthetized rats that were pretreated with isoproterenol to stimulate pineal melatonin production. Animals were killed 15 min after the saline injection, and pineal NAT activity and pineal melatonin levels were measured. The saline injections caused no alteration in the elevated levels of either NAT or melatonin. These data suggest that the disparity in pineal NAT activity (which was high) and pineal melatonin (which was low), in animals swum at night, may not be caused by ANP which is released during strenuous exercise such as swimming.     

Melatonin and photoperiodic time measurement: Seasonal breeding in the sheep

Abstract: Well-established circadian physiology supports the view that photoperiodic time measurement utilizes the coincidence between the presence of light and a photosensitive phase of a 'biological clock' to alter reproductive status—the so-called external coincidence model of seasonal breeding. In this review, we examine the mechanism whereby photoperiod interacts with presumed suprachiasmatic nuclei activity to allow endogenous melatonin to normally synchronize reproductive activity to the optimal time of year. The Romney Marsh sheep is particularly explored as an experimental model. It is suggested that the on/off activity of seasonal reproduction may be a robust mechanism able to be predictably manipulated by the judicious use of the light/dark cycle and exogenous melatonin, but firmly based on circadian principles.     

Response of rat pineal melatonin to calcium, magnesium, and lithium is circadian stage dependent

Abstract: Herein we documented the response of pineal melatonin production to electrolytes known to be effective on pineal function in view of a possible circadian stage dependence. We studied the release of melatonin by perifused rat pineal glands at 2 different circadian stages corresponding to the middle of the light and dark periods, i.e., respectively, 7 and 19 HALO (Hours After Light Onset, L:D = 12:12). The initial efflux rates were, as expected, much higher in the perifusates of glands removed from rats sacrificed during the dark phase than of those removed during the light phase. After 3 hr of perifusion, melatonin release reached similar levels which were found constant up to the 8th hr of perifusion, whatever the circadian stage. Perifusion of the glands with physiological concentrations for the rat of calcium (5.2 mmol/1) and magnesium (1.34 mmol/1) resulted in a stimulatory effect on the pineal glands removed from rats sacrificed in the middle of the dark period (19 HALO), whereas no effects were observed on the pineal glands removed from rats sacrificed during the light (7 HALO). Lithium (0.28 and 0.55 mmol/1) was ineffective on melatonin release in pineal glands removed 7 and 19 HALO. Our results show differences in the initial efflux rates of melatonin and in the response of perifused pineal glands to calcium and magnesium according to the circadian stage.     

Conservative management of perforated duodenal diverticulum： A case report and review of the literature

Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.     

Changes in connexin43, the gap junction protein of astrocytes, during development of the rat pineal gland

Abstract: The abundance of gap junctions between rat pineal astrocytes formed by connexin43 (Cx43) was studied during development. Levels and distribution of Cx43 were measured by immunoblotting and indirect immunofluorescence, respectively. The amount of Cx43 in cells located within the gland was low until about the 7th postnatal day and increased to adult values between the 14th and 21st days postpartum. Although astrocytes, recognized by their vimentin immunoreactivity, were scarce before birth, they were abundant by the 7th postnatal day suggesting that the low levels of Cx43 found at this age corresponded to a low expression of this protein. Localization of the immunoreactivity to Cx43 and vimentin showed a close correlation, indicating that mature or immature pineal astrocytes form gap junctions made of Cx43. Since Cx43 levels attained their adult values at about the time the innervation and the functional state of the gland reached maturity (2–3 weeks after birth), it is proposed that astrocyte gap junctions are involved in the function of the adult rat pineal gland.     

Presence of immunoreactive growth hormone and prolactin in the ovine pineal gland

Abstract: The use of antisera raised against bovine growth hormone (GH) and ovine prolactin (PRL) enabled the detection of related immunoreactive (ir) sequences of proteins in ovine pineal tissue. The isolation of PRL-like ir-material was accomplished using a 0.25 M ammonium sulphate (pH 5.5) extraction followed by ethanol precipitation, whereas the resulting 2.0 M ammonium sulphate (pH 7.0) precipitate contained a GH-like immunoreactivity. Gel chromatography of the GH-like immunoreactivity (Sephadex G-100) indicated the presence of several GH-like fragments ranging in the M_r range of 7,000 to 55,000. Analyses of the PRL-like ir-material found in pineal tissue on HPLC using a TSK 545-DEAE column led to the resolution into a single peak of immunoreactivity. A single peak of activity was also observed following chromatofocusing and hydrophobic interaction chromatography of the ir-peak from the TSK 545-DEAE column. The PRL-like ir-material inhibited the binding of [¹²⁵I]ovine PRL-S14 to anti-ovine PRL antibodies without showing an affinity for binding to anti-rat PRL or anti-bovine GH antibodies. Scatchard analysis of the binding of pineal PRL-like ir-material and pituitary ovine PRL-S14 to liver membranes from day-20 pregnant rats revealed similar affinity constants (K_a of 4.7 ± 0.2 × 10⁹ M^-1). In addition, the replication of Nb 2 Node rat lymphoma cells was stimulated by pineal PRL-like ir-material, an effect known to be specific for lactogenic hormones. The pineal PRL-like immunoreactivity appeared on sodium dodecyl sulfate polyacrylamide gels as a single major band of M_r 24,000. The functional status of PRL-and GH-like ir-material in the ovine pineal remains to be determined, but evidence is presented that the overall protein synthesis rate of the rat pineal responded to circulating concentrations of PRL.