醛固酮对肝星状细胞Ⅰ、Ⅲ型胶原合成及组织金属蛋白酶抑制因子-1 mRNA表达的作用

肾素-血管紧张素-醛固酮系统(RAAS)可能在肝纤维化形成中发挥重要作用，利用醛固酮受体拮抗剂、血管紧张素Ⅱ1型(AT1)受体拮抗剂和血管紧张素转换酶抑制剂(ACEI)等药物阻断RAAS可以显著抑制实验性大鼠肝纤维化的形成。现在体外现察了醛固酮对肝星状细胞株HSC-T6 Ⅰ，Ⅲ型胺原合成和组织基质金属蛋白酶抑制因于-1(TIMP-1)mRNA表达的作用。     

大鼠肝星状细胞表达肾素-血管紧张素-醛固酮系统及其自反馈调节作用

目的明确大鼠肝星状细胞是否表达肾素血管紧张素醛固酮系统(RAAS)的全部成分及其在肝星状细胞激活过程中的变化;观察血管紧张素Ⅱ对肝星状细胞合成RAAS的反馈调节作用;探讨依那普利和氯沙坦对此系统的抑制作用。方法采用原位酶灌注法分离大鼠肝星状细胞,分别在培养第2、4、7天收集上清液,传代细胞用无血清培养,并用不同浓度依那普利和氯沙坦进行干预。采用放射免疫法检测上清液和细胞裂解液中肾素活性、血管紧张素Ⅱ和醛固酮浓度,紫外光法检测血管紧张素转换酶活性,免疫组织化学法检测血管紧张素Ⅱ受体表达,RTPCR法检测RAAS各成分mRNA表达。结果肝星状细胞表达RAAS所有成分mRNA。在肝星状细胞培养上清液中可检测到肾素活性(0.56±0.23)ng·h-1·106细胞-1。血管紧张素Ⅱ(48.79±14.54)pg105细胞和醛固酮(22.75±4.35)pg105细胞,并随肝星状细胞激活升高。依那普利可抑制肝星状细胞表达RAAS;血管紧张素Ⅱ能正反馈调节星状细胞表达RAAS,这种作用可被氯沙坦阻断。结论大鼠肝星状细胞能表达RAAS,并随其激活而升高。RAAS具有自身正反馈调节作用,可被依那普利和氯沙坦阻断。     

缬沙坦对慢性肝病患者肾素-血管紧张素系统的调控及临床意义

研究缬沙坦对慢肝、肝硬化患者肾素—血管紧张素系统(RAS)的影响并探讨其作用机制。54例慢肝、肝硬化患者，随机分为治疗组和对照组。对照组给予常规保肝治疗，治疗组在常规治疗的基础上加用缬沙坦80mg／日，疗程1个月。采用放免法检测治疗前后血清肾素(PRA)、血管紧张素Ⅱ(AⅡ)、醛固酮(ALD)的变化；采用半定量逆转录PCR技术测定治疗组5例慢肝患者缬沙坦治疗前后血管紧张素原mRNA、血管紧张素ⅡⅠ型受体mRNA表达的变化。结果发现经缬沙坦治疗后，血清PRA、AⅡ均较治疗前明显升高，ALD则明显降低。与对照组相比，治疗组治疗后血清RAS各激素水平的变化均有显著性差异，而肝组织血管紧张素原mRNA、血管紧张素ⅡⅠ型受体mRNA的表达较治疗前降低。研究提示缬沙坦可以有效抑制慢性肝病患者循环和肝组织局部RAS的过度激活，对慢肝、肝硬化患者的治疗有一定的积极作用。     

醛固酮促进血管紧张素Ⅱ诱导大鼠心脏成纤维细胞合成胶原

为探讨醛固酮对大鼠心脏成纤维细胞血管紧张素Ⅱ 1型受体表达的影响及醛固酮对血管紧张素Ⅱ促进心脏成纤维细胞胶原代谢效应的影响 ,采用3 H 脯氨酸掺入法对体外分离培养的心脏成纤维细胞分别检测醛固酮、血管紧张素Ⅱ以及二者共同作用后对心脏成纤维细胞胶原合成量的影响 ;分别利用放射配体结合实验和半定量逆转录—聚合酶链反应测定经醛固酮处理后细胞血管紧张素Ⅱ 1型受体及其mRNA的表达水平 ,并比较其与对照组间的差异。结果发现血管紧张素Ⅱ (10 -7mol/L)可使心脏成纤维细胞胶原合成量显著增加 (P <0 .0 1) ,醛固酮对心脏成纤维细胞的胶原合成无影响 ,但醛固酮可明显地增强血管紧张素Ⅱ促进心脏成纤维细胞胶原合成的效应 ;经醛固酮 (10 -7mol/L)处理的心脏成纤维细胞血管紧张素Ⅱ 1型受体的表达与对照组比较明显升高 (2倍 ) ,细胞血管紧张素Ⅱ 1型受体mRNA的水平也较对照组显著增加 (1.5倍 )。结果说明醛固酮虽然不能通过直接作用影响心脏成纤维细胞的胶原代谢 ,但它可以通过上调心脏成纤维细胞血管紧张素Ⅱ 1型受体的表达来增强血管紧张素Ⅱ致心脏成纤维细胞胶原合成增多的效应     

肾素-血管紧张素系统:新成员,新效应

肾素-血管紧张素系统（RAS）通过作用于心血管、肾脏、肾上腺，控制体液、电解质平衡以及动脉压，是机体重要的调控系统。经典的RAS主要成分有肾素、血管紧张素原（AGT）、血管紧张素Ⅰ（AngⅠ）、血管紧张素Ⅱ（AngⅡ）、血管紧张素转换酶（ACE）、血管紧张素受体1（AT1）、血管紧张素受体2（AT2R）。     

血管紧张素原在肝纤维化形成和自发逆转过程中的表达

肾素-血管紧张素系统（RAS）是机体调节血管张力和钠水代谢的内分泌系统，研究表明，多种组织或器官也能合成RAS的全部或大部分成分，以自分泌或旁分泌方式发挥作用，称为局部RAS。局部RAS主要与组织纤维化和（或）重构过程有关，如心肌梗死后纤维化、心肌肥厚、肾纤维化、皮肤纤维化等。肝星状细胞（HSC）表达血管紧张素Ⅱ（AⅡ）、Ⅰ型受体（ATⅠ），并且AⅡ可以促进HSC分裂和增生。为进一步了解组织局部RAS在肝纤维化中的作用，现动态检测了在四氯化碳（CCl4）诱导下大鼠肝纤维化形成与自发逆转过程中，肝脏和肾脏组织血管紧张素原（ANG）、肾素（REN）的表达。     

缬沙坦对肝星状细胞的增殖及胶原合成的影响

对受体生物学功能及肾素血管紧张素系统(RAS)的研究发现，RAS的主要介质血管紧张素Ⅱ(AngⅡ)可诱导纤维化而与其血液动力调节作用无关。研究以肝星状细胞(HSC)系HSC-T6细胞为主要实验对象，探索缬沙坦对AngⅡ引起的HSC-T6细胞的增殖、细胞内钙浓度及胶原合成影响，从而在体外探讨缬沙坦抗肝纤维化的可能机制。     

针对肾素-血管紧张素-醛固酮系统的抗高血压治疗新靶点

尽管近几十年来抗高血压治疗取得了显著的成就,高血压仍是全世界面临的重大挑战,为了寻求更好降压及降压以外的心血管保护,进一步降低心血管风险,有必要研发更有效控制血压的新方法。肾素-血管紧张素-醛固酮系统的调控是目前抗高血压治疗最重要的基石,现阐述针对肾素-血管紧张素-醛固酮系统的抗高血压治疗新靶点,包括血管紧张素Ⅱ的2型受体、中性肽链内切酶、醛固酮合成酶、肾胺酶、肾素（原）受体、肾脏去神经支配、疫苗、血管紧张素转换酶2等。     

内皮型一氧化氮合酶基因与原发性高血压的关系

原发性高血压是多基因的病变，目前作为候选基因研究较多的有血管紧张素原基因、血管紧张素转换酶基因、血管紧张素Ⅱ的Ⅰ型受体基因、α-内收蛋白基因、G蛋白岛亚基基因、肾素基因及内皮型一氧化氮合酶基因等。     

胰腺肾素-血管紧张素系统与临床疾病的相关性

传统肾素.血管紧张素系统(renin-angiotensin system,RAS)被定义为循环相关系统,由血管紧张素原、肾素及血管紧张素转换酶、血管紧张素Ⅱ及其受体等组成,主要参与调节血压、水及电解质平衡.     

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.     

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.     

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.