缺氧时肺动脉内皮细胞与肺动脉平滑肌细胞相互作用对细胞内 …

目的：观察了培养的小牛肺动脉内皮细胞（ＰＡＥＣ）和肺动脉平滑肌细胞（ＰＡＳＭ）于缺氧时对细胞内环核苷酸的影响。结果：ＰＡＥＣ和ＵＰＡＳＭ共培养２４ｈ，ＰＡＥＣ细胞内ｃＡＭＰ含量显著降低（Ｐ〈０．０１），而ＰＡＳＭ细胞内ｃＡＭＰ含量显著增加（Ｐ〈０．０１），二种细胞内ｃＧＭＰ含量显著增加（Ｐ〈０．０１）。缺氧对二种细胞内ｃＧＭＰ含量无显著影响，但能增加ＰＡＳＭ的ｃＧＭＰ含量（Ｐ〈０．０１），降低ＰＡ     

PJ－CW对小鼠脾淋巴细胞内环核苷酸含量的影响

济南假单胞菌细胞壁组分（ＰＪ－ＣＷ）是由我院药物所研制的新型微生物制剂。本文就ＰＪ－ＣＷ对小鼠脾细胞总数及脾淋巴细胞内环核苷酸含量的影响作了动态观察。结果显示：小鼠腹腔注射ＰＪ－ＣＷ后，脾细胞总数在第２～６ｄ明显增多，第８ｄ恢复至对照组水平，脾淋巴细胞内的ｃＡＭＰ含量只在第６ｄ出现短暂下降。ｃＧＭＰ含量在第４～６ｄ明显升高（Ｐ＜０．０５）．ｃＡＭＰ／ｃＧＭＰ比值也只在第６ｄ明显降低（Ｐ＜０．０１）。提示：细胞内ｃＧＭＰ含量升高，ｃＡＭＰ／ｃＧＭＰ比值下降可能导致了细胞分裂过程的启动，增强了脾淋巴细胞的功能。     

缺氧时肺动脉内皮细胞与肺动脉平滑肌细胞相互作用对细胞内环核苷酸的影响

目的：观察了培养的小牛肺动脉内皮细胞（ＰＡＥＣ）和肺动脉平滑肌细胞（ＰＡＳＭ）于缺氧时对细胞内环核苷酸的影响。结果：ＰＡＥＣ和ＰＡＳＭ共培养２４ｈ，ＰＡＥＣ细胞内ｃＡＭＰ含量显著降低（Ｐ＜００１），而ＰＡＳＭ细胞内ｃＡＭＰ含量显著增加（Ｐ＜００１），二种细胞内ｃＧＭＰ含量均显著降低（Ｐ＜００１）。缺氧对二种细胞内ｃＡＭＰ含量无显著影响，但能增加ＰＡＳＭ的ｃＧＭＰ含量（Ｐ＜００１），降低ＰＡＥＣ的ｃＧＭＰ含量（Ｐ＜００１）。ＮＯ合酶抑制剂硝基精氨酸对二种细胞的ｃＡＭＰ含量均无显著影响，但能使常氧培养的ＰＡＥＣ和缺氧培养的ＰＡＳＭ细胞内的ｃＧＭＰ含量显著降低（Ｐ＜００１）。结论：ＰＡＥＣ和ＰＡＳＭ的相互作用可引起第二信使系统传递的变化；缺氧可抑制ＰＡＥＣ的ＮＯ合酶活性而诱导ＰＡＳＭ的ＮＯ合酶活性     

PJ—CW对小鼠脾淋巴细胞内环核苷酸含量的影响

济南假单胞菌细胞壁组分（ＰＪ－ＣＷ）是由我院药物所研制的新型微生物制剂。本文就ＰＪ－ＣＷ对小鼠脾细胞总数及脾淋巴细胞内环核苷酸含量的影响作了动态观察。结果显示：小鼠腹腔注射ＰＪ－ＣＷ后，脾细胞总数在第２～６ｄ明显增多，第８ｄ恢复至对照组水平，脾淋巴细胞内的ｃＡＭＰ含量只在第６ｄ出现短暂下降，ｃＧＭＰ含量在第４～６ｄ明显升高（Ｐ〈０．０５），ｃＡＭＰ／ｃＧＭＰ比值也只在第６ｄ明显降低（Ｐ〈０．０１）     

AC—cAMP—PKA途径对淋巴细胞DNA合成的调节作用

以ＣＤ３ＭｃＡｂ为激动机，以淋巴细胞体外ＤＮＡ合成的研究手段，探讨了ＡＣｃＡＭＰ－ＰＫＡ信号途径在ＣＤ３ＭｃＡｂ诱导的淋巴细胞活化中的意义，研究结果表明ＡＣ，ｃＡＭＰ和ＰＫＡ在决定细胞对外界刺激反应中起着重要作用，在淋巴细胞活化早期细胞内ｃＡＭＰ出现一过性升高，随着细胞活化增殖，ｃＡＭＰ降至正常水平以下，活化ＡＣ，升高细胞内，ｃＡＭＰ水平可显著过性升高，随着细胞活化增殖，ｃＡＭＰ降至正常水平以下，     

AC－cAMP－PKA途径对淋巴细胞DNA合成的调节作用

以ＣＤ３ＭｃＡｂ为激动剂，以淋巴细胞体外ＤＮＡ合成为研究手段，探讨了ＡＣ－ｃＡＭＰ－ＰＫＡ信号途径在ＣＤ３ＭｃＡｂ诱导的淋巴细胞活化中的意义。研究结果表明ＡＣ、ｃＡＭＰ和ＰＫＡ在决定细胞对外界刺激的反应中起着重要作用。在淋巴细胞活化早期细胞内ｃＡＭＰ出现一过性升高，随着细胞活化增殖，ｃＡＭＰ降至正常水平以下。活化ＡＣ、升高细胞内ｃＡＭＰ水平可显著降低ＣＤ３ＭｃＡｂ诱导的淋巴细胞ＤＮＡ合成，而ＰＫＩ却能在一定程度上促进淋巴细胞活化增殖。     

氧化苦参碱对淋巴细胞第二信使的影响

本文研究了氧化苦参碱对淋巴细胞胞浆游离钙、钙摄取功能、ｃＡＭＰ及ｃＧＭＰ水平的影响。结果表明：氧化苦参碱可使淋巴细胞浆游离钙水平上升，其钙离子来源于细胞内储存钙的释放。另外，氧化苦参碱可使ＰＨＡ活化的人扁桃体淋巴细胞的ｃＡＭＰ水平降低。我们推测它可能通过某种方式和细胞膜发生作用，从而影响细胞内钙和ｃＡＭＰ的水平，进而影响细胞功能。     

霍乱毒素对淋巴细胞活化增殖的影响及其机制

研究探讨霍乱毒素（ＣＴＸ）对淋巴细胞活化、增殖的影响及可能的作用机制。研究结果表明，　　ＣＴＸ可显著升高静息ＰＢＭＣ和／或ＣＤ３单抗激活的琳巴细胞内ｃＡＭＰ水平，该效应与ＣＴＸ抑制淋巴细胞增殖和ＩＬ－２的作用密切相关；　　ＡＣ激活剂Ｆｏｒｓｋｏｌｉｎ通过升高细胞内ｃＡＭｐ水平，对于ＣＤ３单抗激活的淋巴细胞增殖有明显的抑制作用；ＣＴＸ不能干扰ＩＬ－２依赖株ＣＴＬＬ细胞的增殖效应，也不影响ＣＴＬＬ细胞内ｃＡＭＰ水平。实验结果提示，ＣＴＸ敏感的Ｇ蛋白亚类参与了ＣＤ３单抗对淋巴细胞活化的调节，ＣＴＸ的抑制作用与其升高细胞内ｃＡＭｐ水平有关。     

创伤后活化T细胞内cAMP代谢,蛋白激酶A活性的变化及意义

研究了创伤小鼠活化Ｔ细胞内ｃＡＭＰ代谢、蛋白激酶Ａ（ＰＫＡ）活性的变化及同Ｔ细胞功能的关系。结果显示，创伤后活化Ｔ细胞内ｃＡＭＰ含量增加，这一变化同创伤后Ｔ细胞白介素２（ＩＬ－２）生成减少，ＩＬ－２受体（ＩＬ－２Ｒ）表达受抑，Ｔ淋巴细胞转化（ＴＬＴ）降低密切相关。创伤后活化Ｔ细胞内腺苷酸环化酶（ＡＣ）、ＰＡＫ活性增加，ｃＡＭＰ－磷酸二酯酶（ｃＡＭＰ－ＰＤＥ）活性降低。ＰＫＡ抑制剂Ｈ－８在体外可明显     

SRBC膜提取物对猪PBMNC第二信使的影响

胰酶水解绵羊红细胞（ＳＲＢＣ）释放膜表面活性蛋白组分Ⅲ（ＴＲＦ－Ⅲ），单独作用可使猪外周血单个核细胞（ＰＢＭＮＣ）胞内ｃＡＭＰ水平升高，以１００μｇ／ｍｌ浓度刺激达最高峰，由对照组０．９４±０．１４ｐｍｏｌ／Ｌ升高到２．７５±０．２５ｐｍｏｌ／Ｌ（Ｐ＜０．０１）。如果ＰＢＭＮＣ事先与腺苷酸环化酶（ＡＣａｓｅ）抑制剂ＬｉC１孵育后再以ＴＲＦ－Ⅲ或ＰＡＨ刺激。ｃＡＭＰ增高受到抑制（Ｐ＜０．０１）；而ＥＤＴＡ－２Ｎａ（一种磷酸二酯酶ＰＤＥ抑制剂）对此ｃＡＭＰ升高无影响。结果提示，此ｃＡＭＰ升高主要是通过活化ＡＣａｓｅ水解ＡＴＰ生成ｃＡＭＰ，而不像是抑制ＰＤＥ减少ｃＡＭＰ降解引起的。ＴＲＦ－Ⅲ诱导猪ＰＢＭＮＣ胞内Ｃａ~(２＋)浓度升高，以１００μｇ／ｍｌ刺激２分钟升高最多，由对照组的２４２±７ｎｍｏｌ／Ｌ升高到３２３±１５ｎｍｏｌ／Ｌ（Ｐ＜０．０１）。以ＥＧ－ＴＡ除去胞外Ｃａ~(２＋)再以ＴＲＦ－Ⅲ或ＰＡＨ刺激，仅观察到小范围［Ｃａ~(２＋)］ｉ升高。看来这一过程包括了刺激胞内Ｃａ~(２＋)释放和胞外Ｃａ~(２＋)内流两种方式。以上结果证明，ＴＲＦ－Ⅲ对淋巴细胞功能影响与细胞内第二信使有关。     

交链孢酚单甲醚对人胎儿食管和胃上皮脂质过氧化的影响

本文报道食道癌高发区粮食中分离的互隔交链孢霉的代谢物交链孢酚单甲醚(AME)在体外攻击人胎儿食管及胃上皮后对相应组织脂质过氧化的影响。采用硫代巴比妥酸试验测定丙二醛含量反映脂质过氧化程度。AME可使胎儿食管及胃丙二醛含量明显升高(P<0.01),其程度与AME剂量相关,说明AME可引发这两器官上皮组织的脂质过氧化。随作用时间的延长,脂质过氧化程度愈来愈高,至4小时达高峰。食管对AME的反应较胃更强烈,提示AME有一定的器官选择性。根据本研究结果。推测AME可能是林县地区人食管癌的病因之一。     

Evaluation of the radioprotective effect of Aegle marmelos (L.) Correa in cultured human peripheral blood lymphocytes exposed to different doses of gamma-radiation: a micronucleus study

The radioprotective effect of a hydroalcoholic extract of Aegle marmelos (AME) was evaluated in cultured human peripheral blood lymphocytes (HPBLs) by the micronucleus assay. The optimum protective dose of the extract was selected by treating HPBLs with 1.25, 2.5, 5, 6.25, 10, 20, 40, 60, 80 and 100 microg/ml AME before exposure to 3 Gy gamma-radiation and then evaluating the micronucleus frequency in cytokinesis blocked HPBLs. Treatment of HPBLs with different doses of AME reduced the frequency of radiation-induced micronuclei significantly, with the greatest reduction in micronucleus induction being observed for 5 microg/ml AME. Therefore, this dose of AME was considered as the optimum dose for radioprotection and further studies were carried out treating the HPBLs with 5 microg/ml AME before exposure to different doses (0, 0.5, 1, 2, 3 and 4 Gy) of gamma-radiation. The irradiation of HPBLs with different doses of gamma-radiation caused a dose-dependent increase in the frequency of lymphocytes bearing one, two and multiple micronuclei, while treatment of HPBLs with 5 microg/ml AME significantly reduced the frequency of lymphocytes bearing one, two and multiple micronuclei when compared with the irradiated control. The dose-response relationship for both groups was linear. To understand the mechanism of action of AME separate experiments were conducted to evaluate the free radical scavenging of OH, O2(-), DPPH, ABTS(+) and NO in vitro. AME was found to inhibit free radicals in a dose-dependent manner up to a dose of 200 microg/ml for the majority of radicals and plateaued thereafter. Our study demonstrates that AME at 5 microg/ml protected HPBLs against radiation-induced DNA damage and genomic instability and its radioprotective activity may be by scavenging of radiation-induced free radicals and increased oxidant status.     

Cyclic nucleotides,possible intracellular mediators of macrophage activation and secretory processes

Macrophages from various sources can be stimulated by a variety of substances to secrete a range of inflammatory mediators and degradative enzymes. The mechanisms involved in the activation and secretory processes are unknown. However, recent evidence suggests that cyclic AMP may play a role in the regulation of neutral protease secretion. Thus, it has been shown that agents known to increase intracellular cyclic AMP levels (cyclic AMP analogues, phosphodiesterase inhibitors, prostaglandin E₁ and E₂, catecholamines, cholera toxin and, indirectly, glucocorticosteroids) inhibit the secretion of the neutral protease plasminogen activator.It is speculated that macrophage activation may also be initiated by changes in the steady-state levels of cyclic nucleotides. A decrease in intracellular cyclic AMP and/or an increase in cyclic GMP levels would favour secretion. It is possible that these changes could be brought about by the action of various stimuli to modify the capacity of the macrophage to synthetize or degrade cyclic nucleotides.     

The regulation of the immune response to polyvinylpyrollidone: antigen induced changes in prostaglandin and cyclic nucleotide levels

Having previously established, that prostaglandins play a role in the regulation of the immune response to polyvinyl pyrollidone, a T-independent antigen, further investigations of the role of prostaglandins and cyclic nucleotides in the control of the immune response to polyvinyl pyrollidone were initiated. Strongly immunogenic (PVP 360,000) and weakly immunogenic (PVP 10,000) molecular sizes of polyvinyl pyrollidone were examined for their effects on splenic PGF2 alpha, PGE and cyclic nucleotide levels. The results show, that PVP 360,000 induces marked changes in PGF2 levels. There is an early marked depression at 2 hours after injection followed by an increase which peaks at 2 hour. At subsequent time intervals (9-10, 13-14 and 16-18 hour) high values were observed, especially in the latter case. cAMP levels undergo significant fluctuations, exhibiting very big rise at 12 and 13 hour post-immunization, cGMP levels are elevated at 2 hour declining thereafter. PGE level in C57Bl mice exhibits very substantial increase at 4-6 hour after immunization, in athymic mice, however, the increase was not significant and was preceded by a profound drop in PGE concentration. PGE level in the splenocytes from athymic mice shows a constant increase till 4 hour after PVP addition, followed by a little decrease at 6-7 hour. cAMP concentration in athymic mice exhibits a drop at 3-4 hour after immunization, followed by an increase at 5-6 hour post-immunization. Indomethacin, an inhibitor of prostaglandin synthetase, blocks the changes in PGF2 and cGMP level but has little effect on cAMP. In contrast, the weakly immunogenic form PVP 10,000 induces a large bimodal increase in cAMP levels peaking at 2 hour and again increasing between 6-8 hour; cGMP levels also rise, but more slowly. The increase in cAMP is blocked by indomethacin even though no comparable increases in PGF2 levels are observed. The changes induced by PVP 10,000 appear to be dependent on T cells since comparable changes are not observed in athymic mice. Although PVP 10,000 is non-immunogenic in normal mice or whole spleen cultures, it is immunogenic in athymic mice and purified B cell cultures. This difference has been traced to an apparent difference in the activation of T cells vs. B cells by PVP 10,000. Lastly, although inhibition of PG synthesis results in an enhancement of the immune response to PVP 360,000, no such enhancement is observed with PVP 10,000. The relevance of prostaglandin and cyclic nucleotide changes to the development of the immune response is discussed.     

Effect of thymosin and lipopolysaccharide on murine lymphocyte cyclic AMP

The effects of thymosin and lipopolysaccharide (LPS) on cyclic AMP levels in lymphocytes were evaluated using three independent assays which included adenine prelabeling, protein kinase binding, and radioimmunoassay. All three assays proved to be both sensitive and accurate in assessing relative changes in lymphocytes after incubation in vitro with various agents. The assays confirmed that basal and stimulated levels of cyclic AMP depended on the origin of the lymphocyte population. Each of the three techniques demonstrated that pyrogen-free bovine thymosin fraction 5 did not elevate thymocyte cAMP levels. In contrast, it was found that lipopolysaccharide (LPS) significantly elevated cAMP levels in both spleen and thymus lymphocytes. These studies indicate that assays for measuring the activity of thymic extracts in which the intracellular levels of cyclic nucleotides are a criterion for activity are only valid if the preparations are not contaminated with endotoxins.     

Adherence of human peripheral blood lymphycytes to measles-infected cells. Enhancement by prostaglandin E1.

We studied the effect of prostaglandins in vitro on an immune reaction mediated by T cells; adherence of lymphocytes to measles-virus-infected human epithelial cells. Normal human lymphocytes adhered to a mean +/- S.D. 20.1 +/- 5.2 per cent of these HEp-2 cells. The percentage positive cells increased to 50.3 +/- 5.7 when lymphocytes were incubated with 10(-6) M prostaglandin E1 (P less than 0.01 vs. untreated lymphocytes); 10(-8) M and 10(-10) M were as effective. Prostaglandin F2alpha had no effect on lymphocyte adherence. Prostaglandin E1 increased lymphocyte cyclic AMP five to 10 times whereas prostagladin F2alpha did not affect cellular levels of this nucleotide. Dibutyryl cyclic AMP (10(-8) M) increased lymphocyte adherence: positive human epithelial cells increased from 16.0 +/- 2.4 to 38.7 +/- 1.1 per cent (P less than 0.01). Prostagladin E1 also increased adherence of lymphocytes from patients with systemic lupus erythematosus from 21.8 +/- 5.8 to 52.5 +/- 9.2 per cent (P less than 0.01). These results indicate that prostagladin E1 and cyclic AMP may serve to stimulate T-cell function and cell-mediated immunity.     

Melatonin potentiates cyclic AMP production stimulated by vasoactive intestinal peptide in human lymphocytes.

The present paper demonstrates the effect of melatonin on cyclic AMP production in human lymphocytes from peripheral blood. Melatonin by itself did not influence cyclic AMP accumulation in these cells at any dose studied; however, the drug potentiated the effect of vasoactive intestinal peptide (VIP) on the cyclic nucleotide production. In the presence of physiological concentrations of VIP (either 1, 10 or 100 pM), melatonin potentiated cyclic AMP production. However, at high doses of VIP (either 1, 10 or 100 nM), melatonin exhibited no such effect. The results suggest that human lymphocytes are a target for melatonin and that it may participate, jointly with VIP, in the regulation of immune function.     

Cyclic nucleotides in the rat caudate-putamen complex: histochemical characterization and effects of deafferentation and kainic acid infusion

Guanosine 3′,5′-cyclic monophosphate (cyclic guanosine monophosphate) and adenosine 3′,5′-cyclic monophosphate (cyclic adenosine monophosphate) were characterized immunohistochemically in the striatum of the rat. Cyclic guanosine monophosphate was associated primarily with fibrillar elements, some of which derived from cell bodies having maximum soma dimensions of 6–10 μm. Cyclic adenosine monophosphate was found primarily in relationship to oval or triangular somata 12–20 μm in maximum extent. Radio-frequency or suction ablations in brain regions—the ventral diencephalon, cortex and thalamus—providing or containing afferents to the caudate-putamen complex produced no effect on histochemical staining patterns or biochemically assessed levels of the two cyclic nucleotides. Loss of immunofluorescence to the two cyclic nucleotides was observed microscopically, however, following intrastriatal infusion of kainic acid; cyclic nucleotides in the non-injected striatum were unchanged. The latter histochemical results could not be corroborated biochemically. Radioimmunoassays showed no net effect of kainic acid on levels of the two cyclic nucleotides in the infused caudateputamen nucleus, whereas levels of these two chemical compounds were increased to 170–219% in the contralateral striatum.It was concluded that, as assessed histochemically, (1) cyclic guanosine monophosphate is primarily associated with glial cells and/or ‘glial-like’ neurons whereas cyclic adenosine monophosphate is found in relationship to neurons and (2) the striatal tissue elements containing these two cyclic nucleotides are organized primarily within the caudate-putamen complex. In addition, (3) immunohistochemical procedures for cyclic nucleotides may assay only tightly bound stores of cyclic nucleotides, whereas biochemical methods may measure both labile and stable pools. This last consideration permits reconciliation of differing results obtained with histochemical and biochemical techniques following intrastriatal infusion of kainic acid.     

Immune interferon production by lymphoid cells: role in the inhibition of herpesviruses.

Bovine peripheral blood lymphocytes (PBL) obtained from infectious bovine rhinotracheitis (IBR) virus- and tuberculin-immunized animals produced large quantities of interferon within 24 h of in vitro stimulation by IBR and purified protein derivative antigens. Separation of PBL into populations enriched in T lymphocytes or B lymphocyte provided the antigen-specific step for immune interferon production. A 2- to 10-fold increase in interferon occurred when lymphocytes were combined with autologous macrophages. Although macrophages, even if treated with antilymphocyte serum to remove any contaminating lymphocytes, could produce some interferon, the augmented interferon produced by macrophage-lypmhocyte cultures was not dmpocytes. Direct physical contact between macrophages and lymphocytes was required for the production of enhanced levels of interferon. Antigen-antibody complexes of irradiated virus-infected cells in the presence of antibody were as efficient or better at stimulating interferon than was free antigen. Because IBR virus was inhibited by interferon levels stimulated in cultures by IBR antigen, it was suggested that the local production of interferon by immune cells might play a similar role in curtailing virus dissemination in vivo, thus leading to recovery from disease.     

Effects of Aegle marmelos (L.) Correa on the peripheral blood and small intestine of mice exposed to gamma radiation.

The radioprotective effect of bael (Aegle marmelos, AME) extract was studied in Swiss albino mice against radiation-induced changes in the peripheral blood, spleen colony forming units, and intestinal mucosa. The mice were treated with 250 mg/kg body weight of AME orally once daily for five consecutive days before exposure to an acute dose of 7 Gy of gamma radiation after the last administration. The peripheral blood was collected and evaluated for red blood cell (RBC), hemoglobin, total leukocyte count (TLC), and lymphocyte count on days one and seven postirradiation. The nucleated bone marrow cells were isolated and tested for colony-forming units (CFUs) in spleen at days one and seven. AME protected mice against the radiation-induced decline in hemoglobin, total leukocyte, and lymphocytes counts and the clonogenicity of hemopoietic progenitor cells assessed by the exogenous spleen colony-forming assay. Irradiation of mice caused a significant decline in the villus height and crypt number with an increase in goblet and dead cells in the small intestine, where the maximum changes were observed on day one postirradiation, indicating a severe damage, and signs of recovery at day seven postirradiation. Treatment of mice with AME before irradiation elevated the peripheral cell count as well as villus height and the crypt number accompanied by a decline in goblet and dead cells when compared with the irradiation control. The recovery and regeneration were faster in AME pretreated animals than the irradiation alone. AME pretreatment significantly decreased lipid peroxidation accompanied by a significant elevation in the GSH concentration in the mouse intestine. The data clearly indicate that the AME significantly reduced the deleterious effect of radiation in the intestine and bone marrow of mouse and could be a useful agent in reducing the side effects of therapeutic radiation.