海洛因依赖者血浆中血栓素和6－酮－前列腺素FIα变化

本文用放射免疫分析法测定了３３例健康人和５７例海洛因依赖者血浆中血栓素（ＴＸＢ＿２）和６－酮－前列腺素ＦＩα（６－Ｋ－ＰＧＦＩα），结果表明，吸食海洛因患者ＴＸＢ＿２，水平高于健康组，６－Ｋ－ＰＧＦＩα水平低于健康组，两者比值海洛因组显著增加，提示ＴＸＢ＿２，与６－Ｋ－ＰＧＦＩα参与海洛因依赖者的发病机制。     

新型免疫抑制剂—FK—506

综述了ＦＫ－５０６的药理作用、药代动力学、临床应用、不良反应、剂量与用法以及药物相互作用。表明ＦＫ－５０６是一个很有发展前途的，用于抗排斥反应的新型免疫抑制剂。     

U—73122对猪子宫平滑肌细胞和胰腺β细胞株RINm5F的电压依赖…

目的：研究Ｕ－７３１２２对细胞内钙离子浓度和电压依赖性钙通道的作用。方法 用Ｆｕａ－２荧光测定胞浆钙浓度和用穿孔膜片箝记录全细胞钙电流。结果：Ｕ－７３１２２呈剂量相关明显地降低ＲＩＮｍ５Ｆ细胞与子宫平滑肌细胞的去极化诱导的钙电流，并抑制ＫＣｌ诱导的与Ｂａｙ－Ｋ－８６４４诱导的胞浆钙浓度的增加。Ｕ－７３１２２的这种作用对子宫平滑肌细胞要比ＲＩＮｍ５Ｆ细胞强，而一种非磷脂酶Ｃ抑制剂Ｕ－３１２２类似物Ｕ     

微生物产生的免疫抑制活性化合物S—9818的研究：Ⅲ.分离和结 …

在寻找新型免疫抑制剂的筛选中,从放线菌ＳＩＩＡ－９８１８的培养液中分离到一个有免疫抑制作用的物质Ｓ－９８１８,基于理化性质和光谱解析,证实其与ＦＫ５０６同质。     

白介素—1受体相关激酶—2反义寡核苷酸对白介素—1和肿瘤坏 …

目的 研究白介素－１受体相关激酶０２（ＩＲＡＫ－２）在白介素－１（ＩＬ－１）与肿瘤坏死因子（ＴＮＦ）激活核因子０ｋＢ（ＮＦｋＢ）过程中的作用。方法 ＩＲＡＫ－２反义胡核苷酸转染人胚在子刺激细胞后,用夹心ＥＬＩＳＡ方法检测ＮＦ－ｋＢ活性。结果以ＩＢＡＫ－２反义寡核苷酸预处理可明显减弱ＩＬ－１诱导的ＮＦ－ｋＢ活性,此效应强度存在时间和浓度依赖性,但ＩＲＡＫ－２反义;寡核苷酸对肿瘤坏死因子话导的ＮＦ－     

芦丁复合物对兔实验性脑梗塞血浆中TXB_2、6－Keto－PGF_（1α）的影响

通过建立兔大脑中动脉阻塞局灶性脑缺血实验模型，测定缺血后及经芦丁复合物治疗后血浆中ＴＸＢ_２、６－Ｋｅｔｏ－ＰＧＦ_（１α）含量。结果发现ＴＸＢ_２在脑梗塞后明显增高，而６－Ｋｅｔｏ－ＰＧＦ_（１α）含量降低，经芦丁复合物治疗后ＴＸＢ_２减少，６－Ｋｅｔｏ－ＰＧＦ_（１α）增高，与缺血组比较有显著性差异（Ｐ＜０．０ｌ）。提示芦丁复合物有明显的调节ＴＸＢ_２／６－Ｋｅｔｏ－ＴＧＦ_（１α）平衡，减轻缺血性脑损伤的作用。     

Sandwich ElISA法测定NF—kB

目的 建立一种操作简便、安全的核因子－ｋＢ活性检测方法。方法 采用夹心酶联免疫吸附测试法,酶标仪,验证夹心酶联免疫吸附测试法,酶标仪,验证ＮＦ－ｋＢ活化的抑制剂反应白介素－１受体相关激酶－２（ＩＲＡＫ－２）寡核苷酸和Ｎ－ａ－Ｔｏｓｙｌ－Ｌ－ｌｙｓｉｎｅ ｃｈｌｏｒｏｍｅｔｈｙｌ ｋｅｔｏｎｅ（ＴＬＣＫ）对ＮＦ－ｋＢ活性的抑制作用。结果 Ｓａｎｄｗｉｃｈ ＥＬＩＳＡ测定结果表明,与对照组相比,用不同     

反义白介素—1受体相关激酶—1;寡核苷酸抑制白介素—1诱导的NF—kB活化

目的：研究反义白素－１受体相关激酶－１（ＩＲＡＫ－１）寡核苷酸对核因子ｋＢ－（ＮＦ－ｋＢ）活化的影响。方法：Ｌｉｐｏｆｅｃｔｉ介导ＩＲＡＫ－１寡核苷酸转染;ｅｐＧ２细胞,以逆转录ＰＣＲ法检测ＩＲＡＫ－１ｍＲＡＮ表达水平,用ＳａｎｄｗｉｃｈＥＬＩＳＡ法检测ＮＦ－ｋＢ的活化。结果;反义ＩＲＡＫ－１寡核苷酸抑制ＩＲＡＫ－１ｍＲＮＡ表达,反义ＩＲＡＫ－１ｍＲＡＮ表达,反义ＩＲＡＫ－１革酸呈剂量（１－８μｇ     

FK506及其在器官移植中的研究进展

ＦＫ５０６是目前已知最强的免疫抑制剂，其主要作用机制可能是通过抑制辅助Ｔ细胞，阻断ＩＬ－２释放，抑制淋巴细胞增殖。因其作用强，不良反应少，目前已作为移植术后免疫抑制剂首选药。本文综述了ＦＫ５０６的药理学及其在器官移植中的研究现状。     

茎点霉299产生的免疫抑制剂Ⅰ.SIPI—299—B,299—O的研究

应用筛选免疫抑制剂的酵母模型,从一真菌茎点霉２９９中分离得到两个活性化合物２９９－Ｂ和２９９－Ｏ。经波谱分析（ＵＶ,ＥＩ－ＭＳ,ＦＡＢ－ＭＳ,＾１Ｈ－ＮＭＲ,＾１３Ｃ－ＮＭＲ－ＤＥＰＴ,＾１Ｈ－＾１Ｈ ＣＯＳＹ,ＨＭＱＣ）,证实它们均为大环内酯化合物,分别与ＶｅｒｒｕｃｒｉｎＡ和Ｂ相同。两个化合物均有强的免疫抑制活性。     

Mitogenic potentials of bestatin, amastatin, arphamenines A and B, FK-156 and FK-565 on spleen lymphocytes

The following aminopeptidase (AP) activities were found to be associated with the surface of mouse spleen cells: Leu-AP (138 pmol/10(5) cells X minute) and AP-B (16 pmol/10(5) cells X minute with Lys-beta-naphthylamide as substrate and 21 pmol/10(5) cells X minute with Arg-beta-naphthylamide substrate); AP-A activity was not detected by the assay system applied. The immunoactive peptide bestatin inhibited the Leu-AP, while AP-B activity decreased in the presence of both arphamenines A and B and bestatin. No effects on these enzymes were caused by amastatin (an AP-A inhibitor), FK-156, FK-565 and Bu-2743E; the latter peptide turned out to be not an inhibitor of cell surface associated microsomal Leu-AP but an inhibitor of cytosolic Leu-AP. The immunoactive peptides bestatin, arphamenines A and B, and amastatin increased [3H]thymidine incorporation into spleen cells containing lymphocytes and macrophages. These mitogenic actions were not observed when macrophages were removed from the cultures or the cells had been stimulated with ConA or LPS. The lactoyl- and heptanoyl peptides FK-156 and FK-565 caused a mitogenic action on lymphocytes independently of the presence of macrophages. The inhibitor of cytosolic Leu-AP did not change the incorporation into lymphocytes.     

Possible nitric oxide modulation in protective effect of FK-506 against 3-nitropropionic acid-induced behavioral,oxidative, neurochemical,and mitochondrial alterations in rat brain

FK-506 is an immunosuppressant being widely used for allograft rejection cases in the present clinical scenario. Recently, the neuroprotective effect of FK-506 has also been reported against a number of neurodegenerative diseases in rodents. This study was designed to explore the possible protective effect of FK-506 and its interaction with nitric-oxide modulators against 3-nitropropionic acid (3-NP)-induced behavioural, biochemical, neurochemical, and mitochondrial alterations in striatum, cortex, and hippocampus regions of the brain. Systemic administration of 3-nitropropionic acid produces Huntington-like symptoms in rats. 3-NP (10?mg/kg) treatment for 14 days impaired locomotor activity, grip strength, and body weight. 3-NP treatment significantly raised malondialdehyde, nitrite concentration, depleted antioxidant enzymes (SOD and catalase), and levels of bioamines (dopamine and norepinephrine) in striatum, cortex, and hippocampus areas of rat brain. Significant alterations in mitochondrial enzyme complexes (I, II, and IV) activities and mitochondrial redox activity have also been altered significantly by 3-NP. Pretreatment with FK-506 (0.5, 1, and 2?mg/kg) significantly reversed these behavioral, biochemical, and cellular alterations. L-arginine treatment with a subeffective dose FK-506 (1?mg/kg) reversed the protective effect of FK-506. However, L-NAME pretreatment with FK-506 (1?mg/kg) potentiated the protective effect of FK-506. The present study shows that FK-506 attenuates 3-NP-induced neurotoxicity and nitric-oxide modulation might be involved in its protective action.     

The effect of immunosuppressive agents (FK-506, rapamycin) on renal P450 systems in rat models.

It is well known that cyclosporin, rapamycin and FK-506 (tacrolimus) are metabolized by the liver microsomal cytochrome P450 enzyme system. Although there have been reports of interaction between these drugs and the renal P450 enzyme system, differences among these immunosuppressants has not been comprehensively demonstrated. We have studied the individual capacities of these immunosuppressants to induce renal microsomal P450 enzymes similar to CYP2B4 and CYP4A2 by examining renal function in treated rats, and have correlated the results by means of biochemical, immunological and immunohistochemical assays of renal P450 enzymes. Cyclosporin caused impairment of renal function with an increase in renal-specific P450 content, but FK-506 and rapamycin did not. Laurate omega- and (omega-1)-hydroxylase activity increased in rats treated with rapamycin but decreased in those treated with FK-506. Prostaglandin A1 (PGA1) omega-hydroxylase activity increased in rats treated with FK-506 but was reduced by treatment with cyclosporin. Aminopyrine N-demethylase activity increased in rats treated with cyclosporin or FK-506, but not in those treated with rapamycin. Western-blot analysis revealed significant induction of P450, (similar to CYP2B4 of the rabbit P450 isozyme) in kidneys from rats treated with cyclosporin but not in those from rats receiving FK-506 or rapamycin. Histochemical studies clearly demonstrated a form of P450 such as CYP4A2 in the proximal tubules of rats treated with cyclosporin, but not in those of rats treated with FK-506 or rapamycin. These results show that although cyclosporin has a strong effect on renal P450 systems and induces such a system in kidney cortex (microsomal P450), FK-506 and rapamycin have no substantial effect on the induction of renal P450. These findings might clarify the nephrotoxicity induced by these immunosuppressive drugs.     

The Acute Effects of FK-506 on Renal Haemodynamics,Water and Sodium Excretion and Plasma Levels of Angiotensin II,Aldosterone, Atrial Natriuretic Peptide and Vasopressin in Pigs

FK-506 has been shown to be an effective immunosuppressive drug with possible nephrotoxic side effects. In this study we have investigated the acute effects of FK-506 on renal haemodynamics, water, sodium and lithium excretion rates and plasma levels of angiotensin II, aldosterone, atrial natriuretic peptide (ANP) and vasopressin in 29 anaesthetized Lancaster/Yorkshire female pigs. A continuous intravenous infusion was given over a 2-h period to 4 groups: A: 0.075 mg kg^?1 (n = 7), B: 0.15 mg kg^?1 (n = 8), C: 0.3 mg kg^?1 (n = 6) and P: placebo vehicle (n = 8). Glomerular filtration rate (GFR) and renal plasma flow (RPF) were measured by the constant infusion clearance technique using 125-I-iothalamate and 131-I-hippuran as reference substances. Hormonal parameters were measured by radioimmunoassay. In all three FK-506 groups, fractional lithium excretion was significantly decreased 2 h after FK506 infusion (P: + 0.4%, A: ? 8.8% (P < 0.05), B: ?12.9% and C: ?11.2% (P < 001 for both). Mean arterial blood pressure (MBP) was significantly increased in the two highest dosage groups (B,C) at 2 h of infusion: (MBP; P: +2.9%, A: +3.5%, B: +12.0%, C: + 15.3% (P < 0.01 for both). GFR and RPF showed minor and inconsistent changes while all other parameters measured showed similar or no changes. In conclusion, acute infusion of FK-506 to pigs does not change overall renal function significantly, but increases mean arterial blood pressure and decreases fractional excretion of lithium.     

Antitumor effects of novel immunoactive peptides, FK-156 and its synthetic derivatives

Effects produced by intratumor or systemic application of FK-156 and its synthetic derivatives on the syngeneic P388-DBA/2 mouse system were investigated. Among 21 compounds tested, FK-156, FK-565, FR-46758, FR-48217, FR-46091 and FR-47920 substantially suppressed tumor growth when directly injected into a tumor mass and further experiments showed that FK-156, FK-565 and FR-46758 were effective even when administered subcutaneously into site remote from tumor. The mechanisms of growth inhibition are strongly suggested to be host mediated, because these three compounds have remarkably low cytotoxicity against P388 cells in vitro. A single dose of FK-565, however, markedly decreased body weight in healthy DBA/2 mice, whereas FK-156 and FR-46758 did not. These results indicate the superiority of FK-156 and FR-46758 as immunotherapeutic agents over FK-565 with respect to their safety for treatment of cancer. Although significant life-span prolongation could not be seen in the two-injection regimen of six compounds in either system, systemic multiple injections of FK-156 and FR-46758 provided a statistically significant increase in the median survival time of P388 tumor bearing mice.     

Effect of FK-506 and cyclosporine on human T and B lymphoproliferative responses.

The macrolide antibiotic FK-506 causes a strong inhibition of human T and B cell proliferation in vitro in concentrations 100-fold lower than cyclosporine (CsA). However, B cell activation appears to be less sensitive to the immunosuppressive action of FK-506 than T cell responses. There was no indication of a synergistic interaction of the two agents. In contrast, CsA added together with FK could counteract the immunosuppressive activity of the latter drug.     

Immunoactive peptides, FK-156 and FK-565. II. Restoration of host resistance to microbial infection in immunosuppressed mice

The immunoactive peptides, FK-156 and its analogue, FK-565 were evaluated in various models of mice immunosuppressed with cyclophosphamide, hydrocortisone, mitomycin C, carrageenan and tumor cells. Treatment with FK-156 (subcutaneous) and FK-565 (oral) markedly restored host defense ability against microbial infection. The therapeutic effect of ticarcillin or gentamicin alone against pseudomonal infection in cyclophosphamide- and hydrocortisone-treated mice and tumor-bearing mice was much lower than in normal mice. The therapeutic effect of these antibiotics against pseudomonal infection in immunosuppressed mice was enhanced markedly by combined use with FK-156. The killing ability of macrophages and polymorphonuclear leukocytes of the immunosuppressed mice was also markedly enhanced by dosing with FK-156.     

Effects of the immunosuppressant FK-506 and its analog FK-520 on hepatic and renal cytochrome P450 mixed-function oxidase.

The novel immunosuppressant FK-506 and its analog FK-520 were found to inhibit the hepatic microsomal mixed-function oxidase system in male Sprague-Dawley rats. At 5 and 10 mg/kg/day, s.c., for 6 days they caused 30-80% decreases in cytochrome P450 levels, NADPH-cytochrome P450 reductase, and benzphetamine N-demethylase activities. The metabolism of FK-506 itself was inhibited by 50%. FK-506 and FK-520 had a minimal effect on the renal cytochrome P450 levels unlike cyclosporin A which produced a 67% increase after six daily 25 mg/kg doses. A single dose of FK-506 (25 mg/kg, s.c.) had a minimal effect on the hepatic or renal metabolizing enzyme system. In vitro, addition of FK-506 and FK-520 to human and control rat liver microsomes resulted in a concentration-dependent inhibition of benzphetamine N-demethylation (10-20% at 50 microM, 60-75% at 250 microM). We suggest that in view of its potential to inhibit hepatic cytochrome P450-dependent mixed-function oxidase, resulting in the inhibition of its own metabolism, FK-506 should be administered with caution to transplant patients.     

Partial inhibition of human neutrophil activation by FK-506 at supratherapeutic concentrations

Summary The macrolide, FK-506, is a potent and effective inhibitor of lymphocyte activation. We studied the effects of FK-506 on human neutrophil activation induced by chemoattractants and by various substances which circumvent receptor stimulation. After preincubation for 5 min at 37°C, FK-506 (1 M) inhibited N-for-myl-L-methionyl-L-leucyl-L-phenylalanine (fMet-LeuPhe)-or platelet-activating factor-induced superoxide production in neutrophils by about 30%. At therapeutic concentrations (0.1–1 nM) FK-506 was ineffective. FK-506 did not inhibit exocytosis and rises in cytosolic Ca²⁺ concentration [Ca²⁺]_i mediated by these stimuli, and it did not at all inhibit neutrophil activation induced by C5a, leukotriene B4 and 4-phorbol 12-myristate 13-acetate. FK-506 (1 M) inhibited A23187-induced exocytosis by about 35%, but A23187-induced superoxide production was unaffected. After preincubation for 5 min at 37°C, FK-506 inhibited fMet-Leu-Phe-induced superoxide production in dibutyryl CAMP-differentiated HL60 cells by about 20%; preincubation with the drug for 24 h did not result in inhibition of superoxide production. FK-506 did not inhibit agonist-binding to formyl peptide receptors and fMet-Leu-Phe-stimulated GTP hydrolysis of heterotrimeric regulatory guanine nucleotide-binding proteins (G-proteins) in membranes from dibutyryl cAMP-differentiated HL,60 cells. FK-506 did not change steady-state and differential polarized phase fluorescence in HL-60 membranes using 1,6-diphenylhexa1,3,5-triene and 12-(9-anthroyloxy)-stearate as probes. Our results show that FK-506 at supratherapeutic concentrations partially inhibits neutrophil activation. Inhibition by FK-506 of fMet-Leu-Phe-induced superoxide production is rapid in onset and is not due to inhibition of agonist-binding to receptors, interference with G-proteins or protein kinase C, reduction of rises in [Ca²⁺]_i or alteration in physical membrane state.Correspondence to R. Seifert at the above address     

FK-506, a novel immunosuppressant isolated from a Streptomyces. II. Immunosuppressive effect of FK-506 in vitro

The immuno-pharmacological profile of a novel immunosuppressive agent, FK-506 produced by a streptomycete, is presented here. We proceeded to test the effect of the agent on various in vitro immune systems. It showed that mixed lymphocyte reaction, cytotoxic T cell generation, the production of T cell-derived soluble mediators such as interleukin 2 (IL-2), interleukin 3 and gamma-interferon and the expression of the IL-2 receptor were suppressed by this agent. The IC50 values of FK-506 and ciclosporin (CS) in all tests were approximately 0.1 nM and 10 nM, respectively. Therefore, the novel agent, FK-506 suppressed in vitro immune systems at about hundred times lower concentration than CS.