依那普利拉通过调控TGF-β1表达对抗AngⅡ诱导的心肌成纤维细胞增殖

目的 探讨血管紧张素转换酶抑制剂依那普利拉(enalaprilat,Ena)对血管紧张素Ⅱ(angiotensinⅡ,AngⅡ)诱导的新生鼠心室成纤维细胞(cardiac fibroblast,CFb)增殖及对羟脯氨酸水平和TGF-β1蛋白表达的影响及机制.方法以培养的新生Wistar大鼠CFb为研究对象,分为对照组,模型组,用药组三个剂量组,采用胰酶消化、差速贴壁法培养CFb,四氮唑盐(MTT)比色法检测细胞增殖;羟脯氨酸法测定胶原含量;逆转录-多聚酶链反应( RT-PCR)和流式细胞仪(FCM)检测Ena对TGF-β1转录及表达的影响.结果 Ena能够显著抑制AngⅡ诱导的CFb增殖(P＜0.05或P＜0.01),降低羟脯氨酸含量(P＜0.05或P＜0.01);抑制TGF-β1转录及其蛋白表达水平(P＜0.05或P＜0.01).结论Ena抗CFb增殖的作用与抑制TGF-β1转录和表达、拮抗AngⅡ的生物效应密切相关.     

伊那普利拉对新生鼠心肌成纤维细胞增殖及作用机制的研究

目的 观察血管紧张素I转换酶抑制剂（angiotensin I converting enzyme inhibitor,ACEI）伊那普利拉（enal-aprilat,Ena）抗血管紧张素Ⅱ（angiotensinⅡ,AngⅡ）诱导的心肌成纤维细胞（CFb）增殖及其对细胞周期蛋白的影响,探讨Ena抗CFb增殖及机制。方法以培养的新生wistar大鼠乳鼠CFb为实验模型,实验分为对照组,AngII组,用药组3个剂量,采用胰酶消化、差速贴壁法培养CFb,四氮唑盐（MTT）比色法检测CFb增殖;羟脯氨酸法测定胶原量;流式细胞仪测定细胞周期和细胞周期蛋白依赖性激酶抑制剂p^27kip1（Cyclin dependent kinase inhibitor,CKI）表达。结果Ena能够抑制AngⅡ诱导的CFb增殖（P〈0.01,P〈0.05）,降低羟脯氨酸含量（P〈0.01,P〈0.05）,增加细胞周期中G0/G1期百分率,降低S期百分率,提高p27kip1表达（P〈0.01,P〈0.05）。结论Ena抑制AngII诱导的CFb增殖与提高p^27kip1表达有关。     

依那普利抗心肌纤维化的作用及机制

目的 探讨依那普利(enalapril,Ena)抗血管紧张素Ⅱ(angiotensinⅡ,AngⅡ)及异丙肾上腺素(Isoprenaline,Iso)诱导的心肌纤维化( myocardial fibrosis,MF)的作用机制.方法 以培养的新生Wistar大鼠乳鼠CFb及在体心脏为模型,实验分为对照组、AngⅡ组、Ena三个剂量组,采用胰酶消化、差速贴壁法培养CFb,四氮唑盐(MTT)比色法检测CFb增殖；羟脯氨酸法测定胶原量；HE染色观察心肌组织形态学和心室重量指数( LVI).结果Ena能够抑制AngⅡ诱导的CFb增殖(P＜0.0l,P＜0.05),降低羟脯氨酸含量(P＜0.01,P＜0.05)；改善心肌形态学变化,降低LVI(P＜0.01,P＜0.05).结论 Ena具有抑制MF作用,其机制可能与抗增殖作用密切相关.     

依那普利拉通过调控PKC/TGF-β1通路抗鼠心室成纤维细胞增殖

目的依那普利拉(Ena)和蛋白激酶C(PKC)抑制剂白屈菜赤碱(Chele)对血管紧张素Ⅱ(AngⅡ)诱导的新生鼠心室成纤维细胞(CFb)增殖、细胞周期、Ⅲ型胶原纤维(CollagenⅢ)、PKC和转化生长因子(TGF-β1)蛋白表达的影响,揭示Ena抗CFb增殖的内在机制。方法培养的新生Wistar大鼠CFb分为对照组、AngⅡ组、Chele+AngⅡ组、Chele+AngⅡ+Ena组和AngⅡ+Ena组,采用胰酶消化、差速贴壁法培养CFb,四氮唑盐(MTT)比色法检测细胞增殖;免疫细胞化学染色(IC)法测定CollagenⅢ含量;流式细胞仪(FCM)检测细胞周期;免疫印迹法(WB)检测PKC和TGF-β1表达。结果与AngII组相比较,Chele和Ena组及Chele+AngⅡ+Ena组能显著降低CFb增殖率(P<0.05或P<0.001)、降低CollagenⅢ含量(P<0.05或P<0.01),提高CFb G0/G1期细胞百分比,降低S期细胞百分比(P<0.05或P<0.01),抑制PKC和TGF-β1蛋白表达(P<0.05或P<0.01)。结论 Ena和Chele能显著抑制由AngⅡ诱导的CFb增殖和间质胶原分泌,可能通过抑制PKC-TGF-β1信号通路实现。     

丹参酮ⅡA抑制大鼠心室成纤维细胞增殖的机制

目的 探讨丹参酮ⅡA(taishinone,TSN)抑制血管紧张素Ⅱ(AngⅡ)诱导的新生大鼠心室成纤维细胞(CFb)增殖的可能机制.方法 将培养的新生Wistar大鼠CFb为研究靶细胞,分为对照组、AngⅡ组、三个剂量药物组,采用胰酶消化、差速贴壁法培养CFb,四氮唑盐(MTT)比色法检测细胞增殖及羟脯氨酸(Hyp)含量;硝酸还原酶法测定CFb中不同时间(24 h,36 h,48 h,60 h)NO水平;比色法测定CFb中SOD活性和MDA含量.结果 TSN能够显著抑制AngⅡ诱导的CFb增殖,降低Hyp含量,呈剂量和时间依赖性升高不同时间点NO水平、提高SOD、降低MDA含量(P＜0.05或P＜0.01).结论 TSN抑制CFb增殖的作用与升高NO水平、提高SOD、降低MDA含量,以及拮抗AngⅡ的生物效应有关.     

异鼠李素对AngⅡ诱导新生大鼠心脏成纤维细胞增殖和胶原合成的影响

目的探讨异鼠李素(Isorhamnetin)对血管紧张素Ⅱ(AngⅡ)诱导新生大鼠心脏成纤维细胞(CFb)增殖和胶原合成的影响.方法建立AngⅡ诱导新生大鼠CFb纤维化模型,采用MTT比色法检测CFb增殖;采用3H-脯氨酸掺入法检测CFb胶原合成,分别观察不同浓度异鼠李素对CFb增殖和胶原合成的影响.结果在一定范围内,异鼠李素以浓度依赖性方式抑制AngⅡ诱导CFb的增殖和胶原合成(P＜0.01).结论异鼠李素具有抑制CFb增殖和胶原合成的作用,对心肌纤维化具有一定的防治效应.     

Benazepril和Losartan对培养SHR心肌成纤维细胞增殖及合成胶原影响

目的　观察血管紧张素Ⅱ (AngⅡ )、苯那普利 (Benazepril,Be na)、洛沙坦 (Losartan)对培养的SHR和WKY大鼠心肌成纤维细胞 (CFb)增殖及合成胶原的影响。方法　采用组织块贴壁法培养CFb ,分别测定AngⅡ、Bena干预下CFb的增殖情况 ,AngⅡ、Bena和Losartan干预下CFb的3H 脯氨酸 (3H Proline)掺入量。结果　各种浓度的AngⅡ (10 -10 mol～ 10 -6mol)和Bena(10 -9mol～ 10 -5mol)对CFb的细胞数显著增殖无影响 ,AngⅡ呈浓度依赖性促进CFb的3H Proline掺入量 ,Bena抑制CFb的3H Proline掺入量 ,Losartan呈浓度依赖性抑制 10 -7molAngⅡ诱导的CFb的胶原合成。结论　AngⅡ和Bena不影响CFb的增殖 ,AngⅡ对CFb的胶原合成有促进作用 ,Bena抑制CFb胶原合成 ,Losartan可拮抗AngⅡ的作用     

厄贝沙坦对AngⅡ诱导的心肌细胞肥大及c-fos mRNA表达的作用

目的在原代培养的新生大鼠心肌细胞上,观察厄贝沙坦对血管紧张素Ⅱ(AngⅡ)诱导的心肌细胞肥大的作用,并研究其对心肌细胞cfosmRNA表达的影响。方法应用细胞培养技术培养新生大鼠心肌细胞,胰酶消化,差数贴壁法体外分离培养大鼠心肌细胞。分干预组和对照组,前者用血管紧张素Ⅱ刺激心肌细胞肥大,厄贝沙坦进行干预;厄贝沙坦进行干预30min后,加入血管紧张素Ⅱ刺激心肌细胞;采用相差显微镜测量细胞大小,测定心肌细胞3H亮氨酸掺入作为心肌细胞肥大的指标;用逆转录聚合酶链式反应(RTPCR)检测心肌细胞cfosmRNA的表达。结果血管紧张素Ⅱ作用24h后,血管紧张素Ⅱ组心肌细胞直径增大(29.2±3.1)μm,高于对照组(18.9±1.3)μm(P<0.05);厄贝沙坦抑制血管紧张素Ⅱ介导的心肌细胞直径增大(20.3±2.1比29.2±3.1)μm(P<0.05)。血管紧张素Ⅱ作用24h后,心肌细胞合成速率血管紧张素Ⅱ组(1951±141)较对照组(1123±121)计数/min·孔明显增加(P<0.01),厄贝沙坦对正常心肌细胞蛋白质合成没有影响(1217±105)计数/min·孔,但能抑制血管紧张素Ⅱ刺激的心肌蛋白质合成速率的增加(1145±142)计数/min·孔(P<0.01)。在培养液中加入血管紧张素Ⅱ作用30min后,心肌细胞cfosmRNA表达明显增加(0.921±0.104,P<0.01),预先加入厄贝沙坦作用30min,可阻断血管紧张素Ⅱ的作用(0.336±0.052,P<0.01)。结论厄贝沙坦可以抑制AngⅡ诱导的心肌细胞肥大,其机制可能与厄贝沙坦抑制了心肌细胞cfosmRNA的表达有关。     

血管紧张素(1-7)对血管紧张素Ⅱ诱导的人脐静脉内皮细胞血凝素样氧化型低密度脂蛋白受体1表达的影响

目的 观察血管紧张素(1-7)对血管紧张素Ⅱ诱导的人脐静脉内皮细胞血凝素样氧化型低密度脂蛋白受体1表达水平的影响并探讨其可能作用机制.方法 采用胰蛋白酶消化法原代培养人脐静脉内皮细胞,取2～5代用于实验,培养的人脐静脉内皮细胞随机分为对照组、血管紧张素Ⅱ组、血管紧张素(1-7)组、血管紧张素Ⅱ+血管紧张素(1-7)组、血管紧张素Ⅱ+血管紧张素(1-7)+血管紧张素(1-7)特异性受体拮抗剂A-779组,通过半定量逆转录聚合酶链反应和流式细胞术分别检测血凝素样氧化型低密度脂蛋白受体1基因和蛋白表达水平;用免疫印迹法检测p38丝裂原活化蛋白激酶磷酸化的表达水平.结果 血管紧张素Ⅱ(10-6mol/L)可以诱导血凝素样氧化型低密度脂蛋白受体1表达增加(P<0.05),血管紧张素(1-7)(10-9～10-6mol/L)随着浓度的增加抑制血管紧张素Ⅱ诱导的血凝素样氧化型低密度脂蛋白受体1表达水平增强(P<0.05);血管紧张素(1-7)特异性受体拮抗剂A-779可阻断血管紧张素(1-7)的上述效应(P<0.05).与对照组相比,血管紧张素Ⅱ(10-6 mol/L)诱导后p38丝裂原活化蛋白激酶磷酸化表迭水平显著增加(P<0.05);血管紧张素(1-7)(10-9～10-6 mol/L)随着浓度的增加抑制血管紧张素Ⅱ诱导的p38丝裂原活化蛋白激酶磷酸化表达水平增强(P<0.05),血管紧张素(1-7)特异性受体拮抗剂A-779可阻断血管紧张素(1-7)的上述效应(P<0.05).结论 血管紧张素Ⅱ可诱导血凝素样氧化型低密度脂蛋白受体1及p38丝裂原活化蛋白激酶磷酸化表达增加,血管紧张素(1-7)抑制血管紧张素Ⅱ的上述效应,并且是通过其特异性受体发挥作用.     

神经酰胺在血管紧张素Ⅱ诱导的内皮细胞凋亡中的作用

目的探讨神经酰胺(CE)是否介导血管紧张素Ⅱ(AngⅡ)诱导的内皮细胞(EC)凋亡。方法体外培养脐静脉EC,分别用血管紧张素Ⅱ1型受体(AT1R)拮抗剂氯沙坦、血管紧张素Ⅱ2型受体(AT2R)拮抗剂PD123319、CE合成酶抑制剂烟曲霉素B1(FB1)预处理细胞,再加入AngⅡ24h后与对照组比较观察细胞凋亡情况;用高效液相色谱(HPLC)检测上述各处理组细胞内CE浓度的变化。结果PD123319和FB1明显减少AngⅡ诱导的EC凋亡(P<0.05),氯沙坦反而增加AngⅡ诱导的EC凋亡(P<0.05);HPLC显示PD123319组和FB1组抑制了CE的合成。结论AngⅡ通过AT2诱导EC凋亡,AT2可以促发CE含量增加。     

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.     

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.     

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.     

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.     

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.     

Microbiology of human immunodeficiency virus anorectal disease

PURPOSE: Individuals who are seropositive for the human immunodeficiency virus are at high risk for opportunistic infection and anorectal disorders. Little prospective information is available regarding anorectal pathogens in these patients. METHODS: One hundred sixty-three HIV-seropositive patients presented to the colorectal clinic between 1989 and 1992. Forty-seven (29 percent) patients were thought to have an infectious process and were prospectively studied using a standardized multiculture protocol. RESULTS: Mean age was 33 (range, 19–59) years. All were male; high-risk behavior accounted for 87 percent of HIV transmissions. Presenting complaints included anorectal pain (79 percent), pus per anum (28 percent), and blood per anum (26 percent). Examination revealed perianal tenderness (60 percent), condyloma (38 percent), perianal ulcers (38 percent), and anal fissures (34 percent). Sixty-six sets of cultures were performed; 28 patients had one set, 15 had two sets, and 4 had three sets. Thirty-two of these 47 patients (68 percent) had positive cultures including herpes (50 percent), cytomegalovirus (25 percent),Neisseria gonorrhoeae (16 percent), chlamydia (16 percent), acidfast bacilli (2 percent), and others (9 percent). Six of 32 patients with positive cultures had more than one organism cultured. Sixteen (50 percent) patients with positive cultures were treated medically, 8 (25 percent) were treated surgically and 8 (25 percent) were treated with both modalities. Sixty-one procedures were performed on 17 patients for condylomata. Eighteen patients had 20 procedures for abscesses, 50 percent of whom had positive cultures for other than common bowel flora; all improved. Fourteen patients underwent 33 procedures for perianal fistulas.Mycobacterium fortuitum was cultured from one patient who required 13 procedures for abscesses and fistulas. Forty-five (96 percent) patients were followed for an average of 12.5 months ±2.9 SEM (range, 1–94 months). Symptoms were improved or resolved in 22 of 32 (69 percent) patients with positive cultures and in 11 of 13 (84 percent) with negative cultures. CONCLUSIONS: Specific pathogens may often be identified in human immunodeficiency virus-seropositive patients with anorectal disorders if aggressively sought. Although patients without specific pathogens identified may be expected to improve with planned empiric treatment, positive identification allows more directed therapy.