PPARγ配体罗格列酮防治实验性心力衰竭大鼠左室重构改善心功能的分子机制研究

目的研究PPARγ配体罗格列酮对心力衰竭大鼠左室重构和心功能及心肌MMPs表达的影响,并探讨其分子机制。方法60只雄性Wistar大鼠分三组:①心力衰竭模型组(CHF,n=25),阿霉素2.5mg/kg,尾静脉注射,每周一次,连续10周;②心力衰竭模型+罗格列酮治疗组(ROS,n=25),ROS3mg/kg,每天1次,灌胃治疗;③正常对照组(CON,n=10)。12周时进行相关指标的检测。结果ROS组较CHF组死亡率降低(20%vs40%,P<0.01)。与CON组相比,CHF组大鼠左室内径扩大,心功能明显下降;ROS组左室内径增加程度降低,心功能指标改善。苦味酸天狼星红染色显示CHF组胶原容积分数(CVF)明显增高(P<0.01);而ROS组纤维化明显减轻,CVF降低(P<0.01)。CHF组左室心肌MMP-2、MMP-9及MT1-MMP表达较CON组明显升高(P<0.01),MMPs明胶酶活性显著增加(P<0.01),ROS组明显抑制MMP-2、MMP-9及MT1-MMP的表达(P<0.01),降低MMPs明胶酶活性(P<0.01),而TIMP-1的表达在三组间差异均无统计学意义(P>0.05)。NF-B活性在CHF组升高(P<0.01),而ROS干预明显降低NF-B活性(P<0.01)。结论PPARγ配体罗格列酮通过拮抗NF-B从转录水平抑制MMPs的表达及活性,进而阻止或延缓心力衰竭左室重构的进展。     

氨甲酰化促红细胞生成素逆转慢性心力衰竭大鼠心肌重塑的作用

目的:观察血清基质金属蛋白酶-2(Matrix metalloproteinase-2, MMP-2)及其组织抑制因子(Tissue inhibitor of metalloproteinase-1, TIMP-1)水平与心肌胶原容积指数(CVF)的变化,探讨氨甲酰化促红细胞生成素(CEPO)对慢性心力衰竭(CHF)心肌重塑的作用及其机制.方法:从80只Wistar雄性大鼠中随机选取10只作为对照组,其余腹腔注射异丙肾上腺素建立CHF模型.5周后将造模成功的大鼠再随机分为2组:CHF组(n=18);CEPO组(n=18),腹腔注射CEPO 50 μg/kg,2次/周,连续4周.CHF组和对照组同期腹腔注射等量0.9%氯化钠溶液.4周后检测3组大鼠血流动力学指标、左心室重量指数(LVMI)和血清MMP-2及TIMP-1水平与CVF的变化.结果:与对照组相比,CHF组左室收缩压(LVSP)、左室内压上升/下降最大速率(±dp/dtmax)绝对值均显著降低(P<0.01),左室舒张压(LVDP)、左室舒张末压(LVEDP)升高(P<0.01),血清MMP-2升高(P<0.01)而TIMP-1降低(P<0.01),LVMI及CVF升高(P<0.01);与CHF组相比,CEPO组大鼠血流动力学各指标变化均有显著差异(P<0.01),血清MMP-2水平降低(P<0.01)、TIMP-1水平升高(P<0.01),LVMI及CVF降低(P<0.01).结论:CEPO有明确的抗心力衰竭作用,通过调节MMP-2和TIMP-1的表达,降解细胞外基质胶原含量,逆转心肌重塑,从而改善心脏功能.     

卡托普利逆转阿霉素心肌病大鼠左室重构机制的研究

目的探讨血管紧张素转换酶抑制剂卡托普利逆转阿霉素心肌病大鼠左室重构和改善心功能的作用机制。方法雄性Wistar大鼠分3组:(1)阿霉素心肌病组(ADR-DCM组,25只):阿霉素2．5 mg／kg,尾静脉注射,每周1次,连续10周;(2)ADR-DCM+卡托普利治疗组(ACEI组,25只):卡托普利50 mg·kg-1·d-1灌胃治疗;(3)健康对照组(对照组,10只)。阿霉素注射2周后行超声和血流动力学检测,硫代巴比妥酸法检测丙二醛(MDA)含量,苦味酸天狼星红染色进行左室胶原特异染色及定量分析,计算胶原容积分数(CVF),RT-PCR检测金属基质蛋白酶(MMP)-2、MMP-9及金属蛋白酶组织抑制因子(TIMP)-1的表达,明胶酶谱法检测MMPs活性。结果ACEI组较ADR-DCM组病死率明显降低(12％和40％,P<0．01)。与对照组比较,ADR-DCM组大鼠左室内径扩大及心功能明显下降,ACEI组左室内径增加程度降低及心功能各项指标改善。ADR-DCM组MDA含量较对照组增加(P<0．01),而ACEI治疗可降低MDA含量。苦味酸天狼星红染色显示ADR-DCM组左室胶原明显增加,CVF增高;ACEI组CVF显著降低(P<0．01)。ADR-DCM组左室心肌MMP-2、MMP-9mRNA表达较对照组明显升高(P<0．01),MMPs明胶酶活性显著增加(P< 0．01),ACEI明显抑制MMP-2、MMP-9mRNA表达,降低升高的MMPs明胶酶活性,而TIMP-1的表达在3组差异无统计学意义(P>0．05)。结论阿霉素心肌病大鼠左室心肌MMPs表达及活性上调,卡托普利部分通过抑制MMPs表达及活性逆转阿霉素心肌病大鼠左室重构,改善心功能。     

葛根素对心肌纤维化模型大鼠左室心肌组织中转化生长因子β_1和结缔组织生长因子表达的影响

目的:研究葛根素对心肌纤维化模型大鼠左室心肌组织中转化生长因子β1(TGF-β1)和结缔组织生长因子(CTGF)表达的影响。方法:采用异丙肾上腺素(5mg·kg-1.d-1×10d)皮下注射诱导大鼠心肌纤维化,给予葛根素(100mg·kg-1.d-1)干预,实验共8周。32只雄性SD大鼠随机分成4组:模型组,空白对照组,葛根素早期干预组,葛根素后期干预组;每组于实验末,计算左室质量指数,取左室心肌组织进行VG染色、免疫组化染色,分别测算胶原容积积分(CVF)、CTGF蛋白和TGF-β1蛋白含量,取左室游离壁心肌组织检测羟脯氨酸浓度和运用RT-PCR半定量分析CTGFmRNA和TGF-β1mRNA水平。结果:葛根素减少模型组大鼠左室质量指数、左室心肌组织CVF及羟脯氨酸浓度(P0.01),模型组大鼠左室心肌组织CTGF和TGF-β1的过度表达(P0.05)。相关分析显示4组大鼠的左室心肌组织CTGF蛋白含量与左室心肌组织CVF和羟脯氨酸浓度呈正相关(P0.05)。结论:葛根素减少心肌纤维化大鼠的左室心肌间质胶原沉积,减轻和延缓大鼠心肌纤维化,这种作用机制可能是通过抑制左室心肌组织中CTGF、TGF-β1的过度表达来实现。     

骨髓间充质干细胞移植治疗心力衰竭

目的 探讨骨髓间充质干细胞移植对阿霉素诱导的心力衰竭大鼠心功能的影响.方法 无菌条件下取8周龄F344大鼠的股骨和胫骨,获得骨髓间充质干细胞(MSCs),在体外纯化、扩增后 ,用5-溴-2'脱氧尿苷(BrdU)进行标记,然后注射到心力衰竭模型细胞移植组和对照组大鼠的心肌组织内,细胞移植后4周,采用生理记录仪测量3组大鼠的心功能 ,处死动物,心脏切片行免疫组化了解移植细胞在受体心脏的存活情况.结果 细胞移植后4周,细胞移植组大鼠死亡率为6.2%,明显低于假细胞移植组12.5%(P<0.01);在受体大鼠的心脏切片上有BrdU标记的移植细胞存活.心功能测定显示:与对照组相比,细胞移植组最大左室收缩末压(LVSP)、心率(HR)、左室内压最大(最小)变化速率(LV±dp/dtmax)均明显下降(P<0.01),而左室舒张末压(LVDP)明显升高(P<0.01);与对照组相比,细胞移植组大鼠的LVSP、HR、LV±dp/dtmax均有明显升高(P<0.01),而LVDP明显降低(P<0.01);与假移植组相比,细胞移植组大鼠的HR、 LV±dp/dtmax仍有明显下降(P<0.01),而LVDP明显升高(P<0.01).结论 MSCs移植可有效改善阿霉素诱导的扩张型心力衰竭大鼠的心功能,减少心力衰竭大鼠的死亡率.     

高脂高糖饮食诱导胰岛素抵抗大鼠心脏功能和心肌Ⅰ型胶原改变及替米沙坦干预的影响

目的 探讨高脂高糖饮食诱导胰岛素抵抗大鼠心脏功能和心肌Ⅰ型胶原改变及替米沙坦干预后对其影响。方法 27只Wistar大鼠随机分为正常对照组(n=9只)、高脂高糖饮食组（n=18只）,高脂高糖饮食干预12周后确定胰岛素抵抗模型建立,将高脂高糖饮食组随机分为高脂高糖组（n=9只）和替米沙坦组（n=9只）。饮食干预34周后颈动脉插管测左室舒张末内压（LVEDP）、左室收缩压（LVSP）和左室内压最大下降速率（-dP/dtmax）。ELISA方法检测血浆中心肌Ⅰ型胶原代谢标志物Ⅰ型前胶原末端的前肽序列(PICP)和Ⅰ型胶原吡啶交联终肽(ICTP)的含量。心肌组织Masson染色进行心肌间质胶原定量分析。结果 与正常对照组比较,高脂高糖组大鼠LVEDP上升,-dP/dtmax下降(P<0.01),血浆PICP含量及PICP/ICTP升高(P<0.01),左室心肌胶原容积分数增高(P<0.01)。与高脂高糖组大鼠比较,替米沙坦组大鼠LVSP、LVEDP均显著下降(P<0.01),-dP/dtmax升高(P<0.05);血浆PICP含量、PICP/ICTP降低(P<0.05)。左室心肌胶原容积分数含量显著下降(P<0.01)。左室心肌组织胶原含量与胰岛素抵抗指数呈显著正相关(R=0.634,P<0.01),与-dp/dtmax呈显著负相关(P<0.01)。结论 胰岛素抵抗大鼠心肌Ⅰ型胶原合成增加,心肌间质胶原沉积增加,心脏舒张功能下降;替米沙坦可改善胰岛素抵抗,减少胰岛素抵抗大鼠心肌Ⅰ型胶原的合成,减少心肌间质胶原沉积,改善心脏舒张功能。     

红景天苷对慢性心力衰竭大鼠心室重构及肾素血管紧张素醛固酮系统的影响

目的探讨红景天苷对慢性心力衰竭大鼠心室重构及肾素血管紧张素醛固酮系统(RAAS)的影响。方法选取SD大鼠行腹主动脉缩窄法制作心力衰竭模型,8 w后取存活的80只模型大鼠随机分为模型组和红景天苷高、中、低剂量组(n=20),红景天苷高、中、低剂量组分别接受24、12、6 mg/kg灌胃处理,每天1次,连续8 w。同时选取20只仅开腹而不结扎的大鼠作为假手术组,假手术组和模型组每天以等量蒸馏水灌胃。比较各组大鼠的超声心动图指标〔左室舒张末内径(LVEDD)、左室收缩末期内径(LVESD)、左心室射血分数(LVEF)、左心室短轴缩短率(LVFS)〕、心室重构相关指标〔心脏指数(CI)、左心室重量指数(LVMI)、心肌胶原容积分数(CVF)、心肌血管周围胶原面积比(PVCA)及心肌羟脯氨酸〕和RAAS指标〔肾素(PRA)、血管紧张素(Ang)Ⅱ和醛固酮(ALD)〕的水平。结果与假手术组比较,模型组的LVEDD、LVESD、CI、LVMI、CVF、PVCA、羟脯氨酸含量及RAAS指标均升高,LVEF、LVFS降低,以上提示造模成功,模型大鼠发生心力衰竭、心室重构及RAAS激活。红景天苷高、中、低剂量组LVEDD、LVESD、心室重构及RAAS相关指标均低于模型组(P0.05),LVEF、LVFS均高于模型组(P0.05)。红景天苷处理的大鼠中,仅高剂量组的羟脯氨酸含量与假手术组的无差异(P0.05)。结论红景天苷能改善心力衰竭大鼠的心功能及心室重构,可能与其改善RAAS激活有关,且以上改善效应与红景天苷的剂量有关。     

卡维地洛对急性心肌梗塞后晚期心室重构影响的实验研究

目的:观察卡维地洛对大鼠急性心肌梗塞后8周心室重构、血清型胶原氨基末端肽(PNP)水平及左心室功能的影响。方法:结扎雄性大鼠左前降支建立急性心肌梗塞模型,术后24h存活的大鼠16只被随机分为:对照组(n=8)、卡维地洛组(n=8,10mg/kg·d,灌胃给药);另设假手术组(n=8)。术后8周导管法测量血流动力学及左心室功能,形态学测算梗塞面积、左心室扩张指数和球形指数;Masson三色染色测量非梗塞区(NIZ)胶原容积分数(CVF);放免法测量PNP水平。结果:对照组与卡维地洛组大鼠梗塞面积无显著性差异(44.70%vs41.79%)。与假手术组相比,对照组左心室舒张末压(LVEDP),左、右心室相对重量(LVRW、RVRW),室间隔厚度(IVST),左心室扩张指数(LVDI),左心室NIZ的CVF、PNP水平均显著增加(P<0.01~0.001);血压、左心室收缩压(LVSP)、左心室球形指数(LVSI)、左心室内压最大上升和下降速度(±dp/dtmax)及其校正值(±dp/dtmax/LVSP)均显著降低(P<0.01~0.001)。与对照相比,卡维地洛组心率、LVEDP、LVRW、RVRW、IVST、LVDI、非梗塞区CVF、PNP水平显著降低(P<0.01~0.001);LVSI、±dp/dtmax及其校正值(±dp/dtmax/LVSP)显著升高(P<0.01~0.001)。血清PNP含量与LVEDP水平呈显著正相关(r=0.8628,P<0.001)。结论:卡维地洛能有效抑制急性心肌梗塞后左心室非梗塞区胶原增生,减轻大鼠急性心肌梗塞后的左心室重构,改善血流动力学和左心室功能。     

缬沙坦对大鼠急性心肌梗死后左室重塑的影响

目的研究缬沙坦对大鼠急性心肌梗死(AMI)后左室重塑的影响。方法将冠脉结扎术后24 h的SD大鼠随机分为心梗组、缬沙坦小剂量组(10 mg·kg-1·d-1)和缬沙坦大剂量组 (30 mg·kg-1·d-1)组,另设假手术组。灌胃给药四周后测定以下指标:(1)左心功能;(2)体重 (BW)、左心室重量(LVM)及左室重量指数(LVMI);(3)心肌梗死面积;(4)左室非梗死区胶原容积分数(CVF。)。结果各心梗组间的心肌梗死面积无显著差别(P>0．05)。与假手术组相比,心梗组左室舒张末压(LVEDP)、INM、LVMI及CVF明显增大,左室收缩压(LVSP)和心室内压最大变化速率 (±dp／dtmax)明显降低(P均<0．01)。与心梗组相比,大剂量缬沙坦可使LVEDP明显降低,±dp／ dtmax明显升高(P<0．01),小剂量缬沙坦对心梗大鼠心功能影响不明显。两种剂量缬沙坦都可明显降低心梗大鼠LVM、LVMI及左室非梗死区CVF,且大剂量缬沙坦较小剂量更显著。结论缬沙坦能够抑制大鼠AMI后的左室肥厚及非梗死区胶原沉积,改善AMI后的左室重塑。     

福辛普利对慢性心力衰竭大鼠心肌细胞凋亡及半胱氨酸天冬氨酸蛋白酶-3的影响

目的探讨福辛普利对慢性心力衰竭(CHF)大鼠心肌细胞凋亡及半胱氨酸天冬氨酸蛋白酶(Caspase)-3表达水平的影响。方法雄性Wistar大鼠50只随机抽取10只为假手术组,其余大鼠采用肾上腹主动脉缩窄法建立大鼠CHF模型,6 w后将成模大鼠随机分为CHF组、Fos10组、FOS20组(福辛普利10、20 mg·kg~(-1)·d~(-1))。治疗8 w后,观察各组大鼠血流动力学指标和左心室重量指数(LVMI);透射电镜观察左室心肌组织形态的改变;TUNEL法检测大鼠左心室心肌细胞的凋亡指数;SP免疫组织化学染色法检测左心室心肌组织Caspase-3蛋白的表达。结果 CHF组与假手术组相比,大鼠左心室舒张末压(LVEDP)、LVMI、心肌细胞凋亡指数、Caspase-3蛋白的表达均明显升高(P<0.01),左心室内压最大上升和下降速率(±dp/dtmax)显著下降(P<0.01);与CHF组比较,Fos10组和Fos20组大鼠LVEDP、LVMI、心肌细胞凋亡指数、Caspase-3蛋白的表达均明显降低(P<0.01),左心室内压最大上升和下降速率(±dp/dtmax)显著升高(P<0.01),且Fos20组效果明显。电镜下观察:Fos10组和Fos20组心肌损伤程度较CHF组明显减轻。结论福辛普利可通过下调Caspase-3的表达抑制心肌细胞凋亡,改善CHF大鼠心室功能及心肌超微结构。     

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.     

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.     

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.     

Serological survey of HIV and syphilis in pregnant women in Madagascar

Objectives Peripartal transmission of human immunodeficiency virus (HIV) and Treponema pallidum, the causative agent of syphilis, leads to severe consequences for newborns. Preventive measures require awareness of the maternal infection. Although HIV and syphilis testing in Madagascar could be theoretically carried out within the framework of the national pregnancy follow‐up scheme, the required test kits are rarely available at peripheral health centres. In this study, we screened blood samples of pregnant Madagascan women for HIV and syphilis seroprevalence to estimate the demand for systemic screening in pregnancy. Methods Retrospective anonymous serological analysis for HIV and syphilis was performed in plasma samples from 1232 pregnant women that were taken between May and July 2010 in Ambositra, Ifanadiana, Manakara, Mananjary, Moramanga and Tsiroanomandidy (Madagascar) during pregnancy follow‐up. Screening was based on Treponema pallidum haemagglutination tests for syphilis and rapid tests for HIV, with confirmation of positive screening results on line assays. Results Out of 1232 pregnant women, none were seropositive for HIV and 37 (3%) were seropositive for Treponema pallidum. Conclusions Our findings are in line with previous studies that describe considerable syphilis prevalence in the rural Madagascan population. The results suggest a need for screening to prevent peripartal Treponema pallidum transmission, while HIV is still rare. If they are known, Treponema pallidum infections can be easily, safely and inexpensively treated even in pregnancy to reduce the risk of transmission.     

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.     

Variabilité des concentrations plasmatiques de l’angiotensinogène et risque d’hypertension artérielle chez le rat transgénique

Aim

Genetic polymorphisms of the human angiotensinogen gene are frequent and may induce up to 30% increase of plasma angiotensinogen concentrations with a blood pressure increase of up to 5 mmHg. Their role for the pathogenesis of human arterial hypertension remains unclear. High plasma angiotensinogen levels could increase the sensitivity to other blood pressure stressors.

Methods

Male transgenic rats with a 9-fold increase of plasma angiotensinogen concentrations and male non-transgenic rats aged 10 weeks were treated or not with NG-Nitro-L-arginine-methyl ester for 3 weeks in their drinking water (n = 3/group). Systolic blood pressure and body weight were measured at baseline and at the end of the study when left ventricular weight and ventricular expression of angiotensin I-converting enzyme and procollagen Iα1 were determined (polymerase chain reaction).

Results

At baseline, transgenic rats had +18 mmHg higher bood pressure and –8% lower body weight compared to non-transgenic rats (P < 0.05) without significant changes for the vehicle groups throughout the study (P > 0.05). NG-Nitro-L-arginine-methyl ester increased blood pressure, left ventricular weight and left ventricular weight indexed for body weight by +41%, +17.6% and +18.6% (P < 0.05) in transgenic and +25%, +5.3% and +6.7% (P > 0.05) in non-transgenic rats compared to untreated animals, respectively. Cardiac gene expression showed no differences between groups (P > 0.05).

Conclusion

Increased plasma angiotensinogen levels may sensitize to additional blood pressure stressors. Our preliminary results point towards an independent role of angiotensinogen in the pathogenesis of human hypertension and associated end-organ damage.