国产西罗莫司洗脱支架与紫杉醇洗脱支架抑制血管内膜增生的血管内超声比较研究

目的利用血管内超声（IVUS）方法比较国产西罗莫司洗脱支架（Firebird^TM）与紫杉醇洗脱支架（Taxus^TM）对冠心病患者新生内膜增生的抑制作用。方法自2003年5月至2007年6月,203例冠心病患者（283处病变）行药物洗脱支架术并在术后1年行冠状动脉造影和血管内超声（IVUS）检查。其中136例患者（185处病变）置入Firebird^TM支架（Firebird组）,67例患者（98处病变）置入TaxusTM支架（Taxus组）。结果203例患者（283处病变）中168例患者（236处病变）接受了一年随访造影和血管内超声检查,其中Firebird组108例患者（147处病变）,Taxus组60例患者（89处病变）。两组患者基础临床情况及造影特征相似。Firebird组支架内晚期管腔丢失（0.17±0.29mm比0.43±0.51mm,P〈0.0001）和节段内晚期管腔丢失（0.18±0.36mm比0.38±0.33mm,P=0.003）明显小于Taxus组,而两组近端参考血管晚期管腔丢失（0.11±0.27mm比0.15±0.32mm,P=0.321）和远端参考血管晚期管腔丢失（0.08±0.10mm比0.09±0.16mm,P=0.483）差异并无统计学意义。IVUS分析显示,两组间平均支架面积、平均管腔面积、最小支架面积、平均支架体积、平均管腔体积比较,差异均无统计学意义。但Firebird组平均内膜增生面积（0.35±0.58mm^2比1.29±1.26mm^2,P〈0.0001）、平均内膜增生面积百分数（5.45%±9.26%比17.38%±13.75%,P〈0.0001）、内膜增生最大面积百分数（9.41%±14.15%比31.56%±20.99%,P〈0.0001）、平均内膜增生容积（2.09±5.46mm^3比13.43±18.59mm^3,P〈0.0001）和平均内膜增生容积百分数（1.68%±5.84%比8.62%±9.90%,P〈0.0001）较Taxus组均明显减少。结论国产西罗莫司洗脱支架（Firebird^TM）置入术后再狭窄发生率较低,与TaxusTM支架相比,抑制内膜增生作用更显著。     

西罗莫司洗脱支架与紫杉醇洗脱支架抑制血管内膜增生的血管内超声比较

目的:利用血管内超声(IVUS)方法比较西罗莫司洗脱支架(CypherTM)与紫杉醇洗脱支架(TaxusTM)对冠心病患者新生内膜增生的抑制作用.方法:自2003-05至2007-04,167例冠心病患者(227处病变)行药物洗脱支架术,并在术后1年行冠状动脉造影和IVUS检查.其中107例患者(138处病变)置入CypherTM支架(Cypher组),60例患者(89处病变)置入TaxusTM支架(Taxus组).结果:两组患者基础临床情况及病变特征相似.造影结果分析显示,Cypher组支架内晚期管腔丢失、节段内晚期管腔丢失明显小于Taxos组[分别为(0.16±0.27)mm比(0.43±0.51)mm,P<0.01;和(0.20±0.32)mm比(0.38±0.33)mm,P=0.01],而两组近端和远端参考血管晚期管腔丢失差异无统计学意义[分别为(0.13±0.29)mm比(0.15±0.32)mm,P=0.689;和(0.08±0.12)mm比(0.09±0.16)mm,P=00500].IVUS分析显示,两组平均支架面积、平均管腔面积、最小支架面积、平均支架体积、平均管腔体积差异均无统计学意义,而Cypher组与Taxus组比平均内膜增生面积[(0.33±0.45)mm2比(1.29±1.26)mm2]、平均内膜增生面积百分数[(5.42±7.33)%比(17.38±13.75)%]、内膜增生最大面积百分数[(10.13±13.85)%比(31.56±20.99)%]、平均内膜增生容积[(2.23±6.50)mm3比(13.43±18.59)mm3]和平均内膜增生容积百分数[(1.59±4.10)%比(8.62±9.90)%],Cypher组均较Taxus组明显减小(P<0.0001),差异均有统计学意义.结论:CypherTM支架治疗冠心病一年再狭窄发生率较低,与TzxusTM支架相比,抑制内膜增生作用更显著.     

国产与进口西罗莫司洗脱支架置入后血管内超声随访的对比

目的 利用血管内超声对比观察国产与进口西罗莫司洗脱支架对冠心病患者支架术后新生内膜增生的抑制作用.方法 2003年5月至2007年3月,对215例冠心病患者(317处病变)置入西罗莫司洗脱支架,并在术后1年行冠状动脉造影和血管内超声(IVUS)检查.其中Firebird组108例患者(147处病变)置入国产西罗莫司洗脱支架(Firebird支架),Cypher组107例患者(138处病变)置入进121西罗莫司洗脱支架(Cypher支架).结果 两组患者一般临床情况差异无统计学意义.两组靶病变部位、病变长度、狭窄程度及病变类型差异均无统计学意义,但Firebird组术后最小管腔直径大于Cypher组[(2.88±0.43)mm比(2.78±0.33)mm,P＜0.05].随访定量冠状动脉造影分析显示,Firebird组与Cypher组支架内晚期管腔丢失[(0.17±0.29)mm比(0.16±0.27)mm,P＞0.05]和节段内晚期管腔丢失[(0.18±0.36)mm比(0.20±0.32)mm,P＞0.05]差异均无统计学意义.IVUS分析显示,与Cypher组比较,尽管Firebird组支架面积[(6.99±2.25)mm~2比(6.46±1.71)mm~2,P＜0.05]、管腔面积[(6.89±2.30)nm~2比(6.36±1.73)mm~2,P＜0.05]、支架体积[(162.5±68.9)mm~3比(140.8±57.9)mm~3,P＜0.01]、管腔体积[(160.4±69.5)mm~3比(138.6±57.6)mm~3,P＜0.01]及最小支架面积[(5.40±1.85)mm~2比(4.92±1.43)mm~2,P＜0.05]均较大,但两组的内膜增生容积[(2.09±5.46)mm~3比(2.23±6.50)mm~3,P＞0.05]和内膜增生容积百分数[(1.68±5.84)%比(1.59±4.10)%,P＞0.05]差异均无统计学意义.结论 Firebird支架置人后再狭窄的发生率较低,抑制内膜增生作用与Cypher支架相似.     

不同支架植入方式对小血管支架内再狭窄的影响

目的:观察不同支架植入方式对小血管（血管直径≤2.75 mm）支架内再狭窄的影响。方法: 对69（男51,女18）例患者共111处病变进行治疗,实验组（n=38）直接植入支架64枚（雷帕霉素药物洗脱支架53枚,紫杉醇药物洗脱支架11枚）,对照组（n=31）预扩张后植入支架47枚（雷帕霉素药物洗脱支架41枚,紫杉醇药物洗脱支架6枚）,两组患者术后即刻行冠脉血管内超声(IVUS)检测最小支架直径及横截面积。术后有胸闷胸痛症状患者即刻行冠脉造影术及IVUS,无症状患者6个月后复查。通过IVUS检测,对两组管腔丢失及支架内再狭窄率进行比较。结果: 两组支架植入术后即刻最小支架直径实验组为（2.38±0.26）mm,对照组为（2.34±0.24）mm（P＞0.05）;支架横截面积实验组为（4.5±1.0）mm2,对照组为（4.3±0.9）mm2（P＞0.05）;6个月随访后复查两组管腔丢失,实验组为（1.44±0.30）mm,对照组为（0.98±0.24）mm（P=0.01）;支架内再狭窄发生率实验组为15 %;对照组为30%（P＜0.05）。结论: 对冠状动脉小血管病变患者直接药物洗脱支架植入组支架内再狭窄发生率低于预扩张后支架植入组。     

介入治疗后有或无冠脉内放射治疗对老年支架内再狭窄的作用和疗效:血管内超声分析

目的　采用血管内超声 (IVUS)评价常规介入治疗术 (CIT)有或无联合冠脉内放射治疗 (IRT)对支架内再狭窄 (ISR)复发的作用及随访观察 1年的临床疗效。方法　 99例ISR的患者经常规介入治疗后随机分为CIT IRT组和CIT组 ,在放疗后即刻和 6个月行IVUS检查 ,分别测量支架、管腔及增生内膜 (IH)面积 ,经计算得到支架、管腔内和IH体积并临床随访 1年。结果　两组基线指标无显著性差异 ,具有可比性。术后 6个月 ,CIT IRT组和CIT组的最小管腔面积 (MLA)各为 (4.30± 2 .0 0 )mm2 与 (2 .81± 2 .56)mm2 (P =0 .0 0 6) ,随访 6个月与放射治疗后即刻MLA差值各为 (- 0 .55± 1 .35)mm2 与 (- 1 .93± 1 .66)mm2 (P <0 .0 0 1 )。CIT IRT组和CIT组的IH体积各为 (69.2 3± 58.57)mm3 与 (1 1 6 .91± 1 2 1 .83)mm3 (P =0 .0 2 1 ) ,随访 6个月与放射治疗后即刻IH体积差值各为 (1 9.50± 35 .90 )mm3 与 (51 .36± 58.80 )mm3 (P =0 .0 1 7)。CIT IRT组 ,随访 6个月 ,MLA≥ 4mm2 的比例明显高于CIT组 (52 .7%与 2 4 .0 % )。术后 6个月 ,冠脉造影显示 ,CIT IRT组和CIT组ISR的复发率分别为 2 4 .53 %与 78.6 % (P =0 .0 2 7)。临床随访 1年 ,CIT IRT与CIT组的主要不利心脏事件 (MACE)、靶血管再次成形术 (TVR)及靶     

血管内超声指导下对冠状动脉严重钙化病变行旋磨介入治疗疗效评估

目的评估血管内超声（IVUS）指导下冠状动脉旋磨术联合药物洗脱支架（DES）治疗严重钙化病变的疗效。方法 13例冠状动脉严重钙化患者在IVUS指导下行冠状动脉旋磨及支架置入术,评估手术即刻成功率、术后管腔最小直径、最小直径狭窄率、管腔有效面积变化及随访结果。结果 13例中,单支病变1例（7.7%）,双支病变3例（23.1%）,三支病变6例（46.2%）,左主干＋三支病变1例（7.7%）,左主干病变2例（15.4%）。术前、术后肌钙蛋白T、肌酸激酶同工酶与肌酸酐比较,差异无统计学意义。靶血管管腔最小直径由术前（2.0±0.3）mm增大至术后的（3.6±0.8）mm,直径狭窄率由术前的（74.5±6.8）%减少至术后的（20.3±12.5）%,管腔有效面积由术前的（4.0±1.4）mm2增大至术后的（10.7±5.5）mm2,差异均有统计学意义。即刻手术成功率100%,术后随访期间无心绞痛再发、心肌梗死及靶血管再次血运重建。结论 IVUS指导下冠状动脉旋磨术联合DES可安全用于冠状动脉严重钙化病变患者,提高了介入手术的成功率。     

血管内超声对复杂冠状动脉左主干病变患者介入治疗的指导价值

目的研究血管内超声(IVUS)对复杂冠状动脉左主干病变患者PCI的指导价值。方法收集2014年1月～2017年1月我科收治的复杂冠状动脉左主干病变并且行PCI的患者110例,分为对照组55例和观察组55例(PCI术中采用IVUS技术进行指导)。比较2组患者基本资料、最小管腔直径(MLD)、最小管腔面积(MLA)、面积狭窄率(AS)、支架直径及长度、支架释放压力、后扩张球囊压力及直径等指标;随访1年,观察2组靶病变血运重建和主要不良心脏事件(MACE)情况。结果观察组MLD[(2.17±0.36)mmvs (1.62±0.59)mm,P=0.000]、MLA[(4.94±1.61)mm~2 vs (2.51±1.77)mm~2,P=0.000]、支架直径[(3.54±0.24)mmvs (3.34±0.31)mm,P=0.002]、支架长度[(14.41±5.25)mmvs (12.11±4.21)mm,P=0.038]、后扩张球囊直径[(3.98±0.51)mmvs (3.77±0.38)mm,P=0.040]、后扩张球囊压力明显大于对照组(P=0.000),AS明显低于对照组[(63.23±8.17)%vs (77.31±7.42)%,P=0.000)];随访期观察组总MACE发生率虽低于对照组,但无统计学差异(9.09%vs 12.73%,P=0.540)。结论 IVUS能有效指导左主干病变PCI支架定位,辅助判断支架扩张和贴壁情况。     

新型生物全降解药物洗脱支架置入小型猪冠状动脉后冠状动脉造影及连续血管内超声评价

目的评价聚左旋乳酸/无定形磷酸钙（PLLA/ACP）新型生物全降解药物支架置入猪冠状动脉6个月内支架弹性回缩及有效性。方法将16枚新型生物支架随机置入小型猪冠状动脉内,行冠状动脉造影检查（术后即刻、随访终点）和血管内超声（IVUS）检查（术后即刻、1个月、6个月）,并且,在术后1个月和6个月分别处死12、4只动物,取支架置入部位血管固定行苏木素-伊红（HE）染色,观察内膜增生情况和支架贴壁情况。结果各小型猪随访终点造影复查可见支架置入段血管血流通畅,无狭窄及血栓形成等现象。IVUS检查提示,平均支架面积和平均支架直径在置入术后1个月和术后6个月时分别与术后即刻比较,差异均无统计学意义[平均支架面积：（6.08±1.30）mm2、（6.00±0.60）mm2比（5.97±0.53）mm2,P〉0.05;平均支架直径：（2.76±0.30）mm、（2.76±0.14）mm比（2.75±0.12）mm,P〉0.05],提示支架未发生显著弹性回缩;病理形态学分析提示,支架置入段血管轻度狭窄,未见支架贴壁不良。结论新型生物全降解支架置入小型猪冠状动脉6个月后,未发现显著支架弹性回缩,具有足够的支撑性能;内膜增生程度较轻,能够保证管腔通畅。     

川芎嗪药物涂层支架预防猪冠状动脉再狭窄的实验研究

目的 探讨川芎嗪药物涂层支架(TES)预防冠状动脉再狭窄的作用机制及其有效性.方法 TES为金属管状支架经喷涂川芎嗪单体制成(含川芎嗪200μg).采用随机、双盲实验在14只小型猪的冠状动脉左前降支分别置入TES及金属裸支架(BMS)(实验组7只,对照组7只).支架置入前后均行定量冠状动脉造影(QCA)及血管内超声(IVUS)检查.术后第28天随访行QCA及ⅣUS观察支架内膜增殖及血栓形成情况.实验终点处死动物,获取支架置入段血管及支架前后5 cm处组织行病理学及免疫组化检查.结果 14只动物均成功置入支架,4只动物因手术意外死亡未列入统计.5只动物于左前降支置入TES,5只动物置入BMs.术后第28天随访,QCA检查支架段血管直径狭窄百分比两组分别为实验组(10.0±2.1)%和对照组(60.2±23.5)%(P=0.01).IVUS检查显示,两组支架内面积相似,均未见血栓形成.对照组内弹力膜面积较实验组明显减小(P=0.021),而新生内膜面积明显增大(P=0.004).术后处死动物组织形态学检查显示两组血管损伤评分和支架内面积相近(P>0.05),均无明显的炎症反应,但实验组管腔面积[(4.34±0.93)mm2]较对照组[(1.29±1.02)mm2]明显增加(P=0.011),新生内膜面积[(1.51±0.45)mm2]较对照组[(4.60±1.39)mm2]明显减少(P=0.004).组织病理学检查提示所有支架置入节段均完全内皮化,实验组增殖细胞核抗原染色阳性细胞核明显减少,凋亡细胞较对照组增多.结论 川芎嗪药物涂层支架能有效抑制血管内膜增殖及血栓形成,减少支架内再狭窄.     

血管内超声指导下对小血管病变的介入治疗

目的评价血管内超声(IVUS)对小血管病变介入治疗的临床意义。方法回顾性分析2010年10月²013年2月于我院接受介入治疗的单支小血管(≤2.5mm)病变患者共237例,其中,IVUS指导下介入治疗的患者105例(Ⅰ组),冠状动脉造影(CAG)指导下介入治疗的患者132例(Ⅱ组)。分析2组患者基线资料、病变特点、介入治疗及随访期间心脏不良事件和再狭窄情况。结果 2组患者介入治疗均成功,Ⅰ组和Ⅱ组置入支架直径[(2.50±0.40)mmvs(2.34±0.37)mm]、支架长度[(28.75±7.77)mmvs(35.78±10.45)mm]、支架高压后扩张(91.4%vs55.3%)和支架内再狭窄(1.9%vs 7.6%)比较,差异有统计学意义(P=0.002,P=0.000,P=0.000,P=0.042);2组串联支架、CAG随访比较差异无统计学意义(P>0.05)。2组患者住院及随访1、3和6个月期间,均无主要不良心脏事件发生。结论对于小血管病变的介入治疗,IVUS具有较好的指导作用。     

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.