幽门螺杆菌长期感染对胃粘膜的影响

目的为了研究Hp长期感染对胃粘膜病变转归的影响.方法随防了63例10年前Hp感染患者,并分析对比10年前后Hp感染情况、胃镜和病理组织学变化.结果①63例患者中16例(25.4%)Hp转阴,47例(74.6%)Hp持续阳性.②Hp持续阳性者10年前后消化性溃疡(PU)的发生率分别为14例(29.78%)和25例(53.19%)(P＜0.05),Hp转阴者10年前后消化性溃疡(PU)的发生率分别为11例(68.8%)和2例(12.5%)(P＜0.05).③Hp持续阳性者10年前后慢性炎症严重程度积分分别为1.77±0.43和2.13±0.34(P＜0.01),肠上皮化生(IM)严重程度积分分别为1.13±0.35和1.63±0.52(P＜0.05);Hp转阴者10年前后慢性炎症严重程度积分分别为1.81±0.40和1.31±0.48(P＜0.01),肠上皮化生(IM)严重程度积分分别为1.6±0.55和1.4±0.59(P＞0.05);Hp持续阳性者10年前后胃粘膜糜烂的发生分别为8例(17.02%)和18例(38.29%)(P＜0.05),IM的发生分别为8例(17.02%)和21例(44.68%)(P＜0.01);Hp转阴者10年前后IM的发生均为5例(31.25%),胃粘膜糜烂10年后完全消失.结论Hp持续感染可增加消化性溃疡的发生机率,加剧胃粘膜的炎症程度,并促进肠化的形成和发展,根除Hp不仅能减轻胃粘膜的炎症程度,而且能阻止肠化的发生和发展.     

幽门螺杆菌长期感染与胃黏膜炎症和肠上皮化生的关系

目的探讨幽门螺杆菌(Hp)长期感染及根除与胃黏膜炎症和肠上皮化生(IM)的关系。方法随访71例5年前和78例10年前Hp感染者,分析对比其前后Hp感染情况、胃黏膜炎症和IM的变化。结果5年前Hp阳性71例中,现在52例(73.2％)Hp仍呈阳性,19例(26.8％)转阴;10年前Hp阳性的78例中,现在59例(75.6％)Hp仍呈阳性,19例(24.4％)转阴。Hp长期阳性者5年前和现在及10年前和现在慢性炎症严重程度积分分别为1.635±0.376与1.808±0.301(P>0.05)和1.661±0.398与2.232±0.335(P<0.01);IM的发生率分别为17.3％(9/52)与26.9％(14/52)(P>0.05)和11.9％(7/59)与39.0％(23/59)(P<0.01);IM严重程度积分分别为1.444±0.527与1.667±0.442(P>0.05)和1.571±0.534与2.286±0.488(P<0.05)。Hp转阴者5年前和现在及10年前和现在慢性炎症严重程度积分分别为1.684±0.369与1.369±0.426(P<0.05)和1.647±0.389与1.182±0.396(P<0.01);IM的发生率为31.6％(6/19)和52.6％(10/19);IN严重程度积分分别为1.333±0.516与1.167±0.775(P>0.05)和1.600±0.516与1.100±0.316(P<0.05)。结论Hp感染持续时间越长,胃黏膜炎症越严重,IM程度亦越严重且发生率高;根除Hp不仅能减轻胃黏膜的炎症程度和IM程度,而且能防止IM的发生。     

胃黏膜炎症和肠上皮化生与幽门螺杆菌长期感染分析

目的 探讨幽门螺杆菌(Hp)长期感染及根除与胃黏膜炎症和肠上皮化生(IM)的关系.方法 随访142例4年前和156例7年前Hp感染者,分析对比其前后Hp感染情况、胃黏膜炎症和IM的变化.结果 4年前Hp阳性142例中,现在104例(73.2%)Hp仍呈阳性,38例(26.8%)转阴.7年前Hp阳性的156例中,现在118例(75.6%)Hp仍呈阳性,38例(24.4%)转阴.Hp长期阳性者4年前和现在及7年前和现在的慢性炎症严重程度积分分别为1.635±0.376与1.808±0.301(P＞0.05)和1.661±0.398与2.232±0.335(P＜0.01);IM发生率分别为17.3%(18/104)与26.9%(28/104)(P＞0.05)和11.9%(14/118)与39.0%(46/118)(P＜0.01);IM严重程度积分分别为1.444±0.527与1.667±0.442(P＞0.05)和1.571±0.534与2.286±0.488(P＜0.05).Hp转阴者4年前和现在及7年前和现在的慢性炎症严重程度积分分别为1.684±0.369与1.367±0.426(P＜0.05)和1.647±0.389与1.182±0.396(P＜0.01);IM的发生率为31.6%(12/38)和52.6%(20/38);IM严重程度积分分别为1.333±0.516与1.167±0.775(P＞0.05)和1.600±0.516与1.100±0.316(P＜0.05).结论 Hp感染持续时间越长,胃黏膜炎症越严重,可能IM程度亦越严重,且发生率高;根除Hp不仅能减轻胃黏膜的炎症程度和IM程度,也可能防止IM的发生.     

胃黏膜炎症和肠上皮化生与幽门螺杆菌关系的远期观察

[目的]远期追踪幽门螺杆菌(Hp)相关胃炎及Hp阴性的胃炎胃黏膜炎症和肠上皮化生(IM)在病程演变中的关系.[方法]经胃镜检查确诊的Hp阳性胃炎86例(A组),Hp阴性的胃炎92例(B组),对照观察两组5年前后的逆转变化,胃黏膜炎症和IM的程度积分.[结果]5年后A组86例中Hp阳性者61例(70.9%)、转阴者25例(29.1%);5年后两组Hp阳性者、5年前后的炎症程度积分差异无统计学意义;B组Hp阴性者、A组Hp阳性者5年前后比较差异无统计学意义;5年后B组中Hp仍阴性者与A组Hp仍阳性者,其胃黏膜炎症和IM积分比较差异有统计学意义(P＜0.01).[结论]Hp在胃黏膜内存在的时间越长,其炎症和IM的程度越重,发生率也增加,而Hp阴性的胃炎和Hp阳性胃炎转阴后其炎症和IM的程度及发生率均有下降.     

灭Hp胶囊多联治疗Hp阳性消化性溃疡

目的寻求中西医结合治疗Hp相关性消化性溃疡(PU)的理想方案方法采用前瞻性、随机双盲、安慰剂对照研究Hp阳性的PU患者93例被随机分为4组A组(新三联)达克普隆30mg,1次/d+阿莫西林500mg,2次/d+克拉霉素250mg,2次/d,连服10 d;B组(灭Hp胶囊四联)新三联10d+灭Hp胶囊6粒,2次/d,连服28 d;C组(灭Hp胶囊三联)达克普隆30 mg,1次/d+克拉霉素250 mg,2次/d,连服10 d,+灭Hp胶囊6粒,2次/d,连服28 d,D组(安慰剂)胃舒平3片,2次/d,连服28 d.双盲双模拟用药.结果 Hp根治率在B,C组与A组分别为96%,92%和92%;溃疡愈合率分别为100%,92%和88%,三组间差异无显著性,明显高于D组的HP根治率(0%)和溃疡愈合率(20%)(均P＜0.01).B,C组溃疡愈合质量明显优于D组,也优于A组B,C组治疗后胃粘膜磷脂(mg/g,93±26.92±27)、氨基己糖(mg/g,55±20,53±15)和血清表皮因子(EGF)(μg/L,0.7±0.3,0.6±0.4)含量明显高于治疗前磷脂(mg/g,79±23,81±23,均P＜0.01)、氮基己糖(mg/g,40± 14;42±16,均P＜0.01)和EGF(μg/L,0.5±0.2,P＜0.01;0.5±0.3,P＜0.05)含量.A组治疗后仅氨基己糖含量(49 ± 18)高于治疗前(42±16,P＜0.05),磷脂和EGF无明显变化.D组磷脂、氨基已糖和EGF治疗前后无明显变化(P＞0.05)各项检测指标B组优于C组,但无统计学意义治疗期间患者依从性好,无不良反应发生.结论中西医结合灭Hp胶囊三联、四联疗法除了有Hp根除与溃疡愈合率高,而乏副作用外,还具有保护胃粘膜,溃疡愈合质量高的特点,是治疗Hp相关性PU的较为理想方案.     

十二指肠球部幽门螺杆菌定植与细胞增殖及溃疡形成的关系

目的探讨幽门螺杆菌(Hp)相关性球粘膜病变的病理机制,阐明Hp在溃疡形成中的作用.方法自未有心、肺、肝、胆、肾疾病及近期服用非甾体类消炎药、饮酒和大量吸烟而因不同消化道症状接受内镜检查的患者中,随机选取经内镜诊断的正常球粘膜32例、十二指肠炎57例、霜斑样病变42例和球溃疡(DU)62例,各组年龄构成无显著差异.患者空腹行电子内镜(GIF-V230)检查.先于DU边缘、病变区或正常球前壁取材2块;再于距幽门5cm以内胃窦小弯侧取材1块.按试纸盒(珠海珠信生物公司)说明行快速尿素酶试验再涂片Giemsa染色检测Hp;另以10%福尔马林固定的球粘膜标本中,5例太小予以剔除,其余连续切片行常规病理检查,并经微波炉抗原修复后以PCNA单抗(PC10鼠抗人1:50稀释)行SP免疫组化(美国Zymed公司)检查.参照文献[中华消化杂志,1998;18:259]与[实用内科杂志,1982;1:18-19],以科研标准判断Hp感染程度,按文献[临床与实验病理杂志,1998;14:331-333]与[世界华人消化杂志,1999;8:649-651]分别判断炎症与PCNALI.分析球部Hp与这些指标的关系.结果行X2检验、t检验、Nemenyi秩和检验及Spearman rank分析.结果球部Hp的检出率:正常球粘膜、球炎、霜斑样病变与溃疡分别为15.6%,36.8%,78.5%,55.7%,在不同病变间存在显著差异(P<0.05),与胃窦Hp密度相关(rs=0.5566,P<0.05);球粘膜炎症程度:正常组中,0,Ⅰ,Ⅱ,Ⅲ级分别为19,6,6,0例,球炎组中分别为10,16,26,3例,霜斑样病变中分别为0,2,18,21例,球溃疡组中分别为1,18,25,16例,在不同病变间也存在显著差异(P<0.05),与球部Hp定植密度相关(rs=0.5615,P<0.05).细胞增殖指数(PCNALI)球部Hp阳性组27.39±8.9,高于Hp阴性组8.80±7.68(P<0.05),并随炎症程度升高:0,Ⅰ,Ⅱ级,其PCNALI分别为9.38±1.99,15.22±2.61,26.22±7.07,彼此间差异显著(P＜0.05),但Ⅲ级27.79±9.85,与Ⅱ级间无显著差别(P＞0.05).霜斑样病变处Hp阳性率最高(P＜0.05),炎症最重(P＜0.05),其与DU的PCNALI分别为26.79±9.15,26.08±9.55无显著差异(P＞0.05),均显著高于球炎18.69±7.32(P＜0.05),所有病变粘膜的Hp阳性率、炎症程度及PCNALI均显著高于正常球粘膜(P＜0.05).结论 Hp相关性球炎的炎症程度取决于Hp定植的密度,受胃窦Hp密度的影响;可能因重度炎症时细胞增殖与凋亡的失衡而发生糜烂或溃疡.     

幽门螺杆菌感染对胃黏膜环氧合酶-2表达的影响

目的评估幽门螺杆菌(Hp)感染对慢性胃炎胃黏膜环氧合酶-2(COX-2)表达的影响.方法与10例正常对照者比较,用免疫组化方法半定量检测46例慢性胃炎患者Hp根除治疗前后胃窦黏膜COX-2蛋白的表达,用悉尼分类标准对胃黏膜炎症、活动性和Hp密度进行半定量测定.结果在胃黏膜表面上皮、腺上皮细胞和固有层间质细胞的胞浆中可见COX-2表达.与正常对照者比较,Hp感染胃黏膜的COX-2平均阳性细胞率明显增加[(18.0±14.1)%比(12.3±4.6)%,P＜0.05)];成功根除Hp后的胃黏膜COX-2平均阳性细胞率明显下降[(20.1±13.1)%比(13.8±5.9)%,P＜0.05)];COX-2表达与慢性炎症计分相关(r=0.78,P＜0.05).结论Hp感染导致胃黏膜COX-2表达增加,提示COX-2在Hp相关性胃炎发生中起作用.     

胃癌中幽门螺杆菌感染与癌基因蛋白表达及凋亡

目的　研究幽门螺杆菌 (Hp)感染的胃癌 (GC)发展过程中c met蛋白表达与细胞凋亡的关系及对胃癌预后的意义。方法　对 14 5例经病理证实的不同胃粘膜病变采用免疫组化法检测c met基因表达及Warthin starry法检测Hp感染。采用原位末端标记法 (TUNEL)检测细胞凋亡。结果　在浅表性胃炎 (CSG)、萎缩肠化生胃炎 (CAG +IM )、异型增生 (DYS)、早期GC和进展期GC中 ,c met基因表达率分别为 2 5 .5 3 %、5 1.2 8%、6 1.5 4%、6 6 .6 7%和 6 8.42 % ,CAG +IM、DYS、GC的c met基因表达率均显著高于CSG (P <0 .0 5 )。凋亡指数 (AI)分别为( 4 .5 5± 2 .33) %、( 6 .43± 5 .6 0 ) %、( 6 .45± 5 .12 ) %、( 6 .5 5± 4.80 ) %和 ( 8.84± 5 .6 3) % ,进展期GC显著高于CSG(P <0 .0 5 )。胃粘膜凋亡指数与c met表达强度密切相关 (P <0 .0 5 )。c met阳性表达与胃癌组织类型、浆膜浸润和淋巴结转移密切相关 ,而且BorrmannⅣ明显高于早期胃癌和BorrmannⅠ ,Ⅱ (P <0 .0 5 )。Hp阳性者 5年生存期显著短于Hp阴性者。 结论　Hp感染和c met表达与胃粘膜增殖和恶化有关 ,且与凋亡有相关性。Hp感染与胃癌预后有关。     

胆汁反流性胃炎患者幽门螺杆菌感染及其胃粘膜病理学表现研究

目的探讨胆汁反流性胃炎(BRG)患者幽门螺杆菌(Hp)感染及其胃粘膜病理学变化。方法我院诊治的BRG患者618例和无胆汁反流的慢性浅表性胃炎(CSG)患者1486例,采用~(14)C-尿素呼气试验、血清抗-Hp抗体检测和对组织切片行硼酸亚甲蓝染色三种方法对受试者进行Hp感染诊断,常规行胃镜检查,参照新悉尼系统标准,将组织学上胃黏膜慢性炎性反应、炎性反应活动性、萎缩和肠上皮化生的严重程度分为无、轻、中和重4个等级。结果 BRG患者Hp感染率为32.7%(202/618),而CSG组患者为40.6%(603/1486),两组间无显著性差异(P0.05);在202例Hp阳性的BRG患者中,胃粘膜轻、中、重度炎症反应发生率分别为10.9%、61.4%和27.7%,显著重于416例Hp阴性患者的40.4%、51.7%和7.9%(P0.05),胃粘膜淋巴滤泡形成、肠化生和活动性炎症发生率分别为15.4%、5.4%和16.8%,也显著重于Hp阴性患者的2.7%、10.8%和0.7%(P0.05);603例Hp阳性的CSG患者胃粘膜轻、中、重度炎症反应发生率分别为29.2%、59.4%和11.5%,与883例Hp阴性患者的34.1%、54.0%和11.9%比,无显著性差异(P0.05),胃粘膜淋巴滤泡形成、肠化生和活动性炎症发生率分别为10.4%、1.8%和8.5%,与Hp阴性患者的7.8%、1.0%和5.0%比,也无显著性差异(P0.05);观察胃粘膜病理学轻度、中度和重度炎症情况发现,117例内镜下胃粘膜Ⅲ级BRG患者炎症程度显著重于200例Ⅰ级或301例Ⅱ级患者(P 0.05)。结论 BRG患者无论是胃镜下表现还是胃粘膜组织病理学变化都存在明显的病变,胆汁反流和Hp感染是引起胃粘膜炎症反应的重要因素。     

根除Hp与疗胃煎剂对Hp相关CAG治疗作用

目的研究根除Hp与疗胃煎剂对Hp相关CAG的治疗作用.方法实验研究,90 g～110 g,二级Wistar大鼠70只,随机分为疗胃煎剂治疗组(三种不同剂量)、三九胃泰对照组、单纯根除Hp组、自然恢复组与正常组(各10只).采用灌胃接种SS1Hp菌株,灌胃水杨酸钠溶液,交替自由饮用50mL/L乙醇与5 mmol/L去氧胆酸钠溶液的综合方法制备Hp相关CAG动物模型.模型制备成功后均先根除Hp,以三九胃泰为对照进行疗胃煎剂治疗,12 wk疗程结束后,处死动物进行Hp感染,病理组织学检查与粘膜氨基己糖含量检测.临床研究,34例经内镜、病理证实的Hp阳性CAG患者随机分为疗胃煎剂治疗组和硫糖铝对照组,治疗前后分别进行病理组织学及化验指标检测.结果实验研究结果显示,疗胃煎剂中、高剂量组大鼠粘膜萎缩程度较三九胃泰组,自然恢复组及单纯根除Hp组明显减轻[粘膜上皮层厚度(pm)分别为97±14,96±13,73±11,66±12,74±10,P＜0.05],中剂量组粘膜氨基己糖增加,与自然恢复组比较(22.53±4.37)mg/gvs(12.21±2.40)mg/gP＜0.05.自然恢复组Hp均为阳性,粘膜固有层有较明显炎症细胞浸润.其他各实验组Hp阴性,粘膜固有层无明显炎症反应.临床研究结果显示,疗胃煎剂对萎缩病变治疗有效率75%(15/20)明显高于硫糖铝组29%(4/14)(P＜0.01),粘膜氨基己糖含量增加(41.21±7.73,49.72±12.61,P＜0.05).硫糖铝对照组治疗前后无明显变化.结论疗胃煎剂具有增强胃粘膜屏障功能作用,可增加氨基己糖含量,能增加粘膜固有层厚度,是治疗CAG的有效药物.     

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.     

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.     

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.     

Morphological and immunocytochemical heterogeneity of cultured pinealocytes from one-week-and two-month-old rats: Planimetric and densitometric investigations

Abstract: In vitro preparations of rat pinealocytes are widely used for biochemical analyses of signal transduction processes. This paper deals with morphological and immunocytochemical features of such preparations. Special attention was paid to the problems of whether pinealocytes represent a heterogeneous cell population and how such heterogeneity may develop during ontogeny. The investigations were performed with cells which were obtained from the pineal organ of one-week-and two-month-old rats, attached to synthetic peptide-coated coverslips or tissue culture chamber slides, and maintained under in vitro conditions overnight. The attached cells were then fixed with paraformaldehyde. These preparations yielded monolayers of spherical cells of different sizes; most cells were isolated, but some of them were aggregated and formed small clusters. On the average, the cells from the one-week-old animals were smaller than the cells from the two-month-old animals. Immunocytochemical demonstration of S-antigen, a pinealocyte-specific marker, showed that the majority of the cells from two-month-old animals were intensely or moderately labelled. Pinealocytes from one-week-old animals were less S-antigen immunoreactive. Only very few cells (less than 1% displayed glial fibrillary acidic protein (GFAP)-immunoreactivity. Planimetric investigations of the cell size and semiquantitative densitometric investigations of the intensity of the S-antigen immunoreaction revealed that (i) pinealocytes kept in vitro form a heterogeneous cell population, and that (ii) this heterogeneity increases during postnatal development from one-week-old to two-month-old animals. Two groups of pinealocytes can be distinguished based on their developmental fate: pinealocytes of one group grow dramatically, but show only a moderate increase in S-antigen immunoreactivity, and pinealocytes of the other group retain their size, but display a distinct increment in S-antigen immunoreacti vitv.     

MUTATION FREQUENCY IN NURSES AND PHARMACISTS WORKING WITH CYTOTOXIC DRUGS

Individuals occupationally exposed to cytotoxic drugs may be at risk owing to the effects of these agents on DNA. As an index of DNA damage, in vivo mutations were measured in lymphocytes from 24 oncology nurses or pharmacists and 24 matched controls. Mutation frequency was significantly increased in exposed individuals and appeared to be related to duration of exposure. However, the overall magnitude of the increase was small and its biological significance remains to be determined.