Gosset P, Shirali P, Marez T, Boutin A C, Balduyck M, Huet G, Venembre P, Haguenoer J M
GIP-CERESTE Institute of Occupational Medicine, Lille, France.
Cent Eur J Public Health. 1996;4 Suppl:56-7.
The association of small quantities of ferric oxide with Benzo[a]Pyrene (BaP) appears to increase in vivo the toxic effect of BaP. The effect of Fe2O3 may be mediated by the recruitment of alveolar macrophages. These cells would contribute to the production of toxic and carcinogenic BaP metabolites and would stimulate development of tumors by producing cellular mediators of inflammation. In order to understand the mechanism of the synergic effect, we have instillated male Sprague Dawley rats 3 weeks of age with a single dose: Fe2O3 (3 mg) or BaP (3 mg)/combination Fe2O3-BaP (3 mg-3 mg) in 200 microliters of physiological saline solution. Control group of identical size (treated with physiological saline solutions and untreated) were used for this study. Animals were sacrificed 48 hours after instillation and a bronchoalveolar lavage (BAL) was performed. With each BAL we have obtained protein measurement, cells were stained with May-Grünwald-Giemsa method and slides were studied with polarised light. The malonaldehyde (MDA) was measured by High Performance Liquid Chromatography. The PMN elastase determination was performed by IMAC (immuno-activation) technology. An automated kinetic method for measuring cathepsins B and L was carried out using a fluorogenic substrate: Z-Phe-Arg-AMC, a specific inhibitor E64 and AMC as an internal standard. After a quantitative Dot-Blot of the samples of BAL, an immunodetection of alpha(1)-antitrypsin (alpha(1)AT) was performed. The inhibitory capacity of alpha(1)AT was determined by an enzymatic reaction with porcine pancreatic elastase. We have observed an increased MDA level for rats intoxicated with Fe2O3 (123%), BaP (31%) and Fe2O3 + BaP (56%). The levels of PMN elastase and cathepsin B and L were increased: Fe2O3 (51-58%), BaP (52-27%). This effect was not seen for rats intoxicated by Fe2O3 + BaP. The free alpha(1)AT was decreased with the three toxics (Fe2O3: 44%--BaP: 42%--Fe2O3: 41%). The inhibitory capacity of alpha(1)AT was lower in groups of rats instilled with toxics.
少量氧化铁与苯并[a]芘（BaP）的结合似乎会在体内增强BaP的毒性作用。Fe2O3的作用可能是通过募集肺泡巨噬细胞来介导的。这些细胞会促使产生有毒和致癌的BaP代谢产物，并通过产生炎症细胞介质来刺激肿瘤的发展。为了了解协同作用的机制，我们给3周龄的雄性Sprague Dawley大鼠单次滴注：Fe2O3（3毫克）或BaP（3毫克）/Fe2O3 - BaP组合（3毫克 - 3毫克），溶于200微升生理盐溶液中。使用相同大小的对照组（用生理盐溶液处理和未处理）进行本研究。滴注后48小时处死动物并进行支气管肺泡灌洗（BAL）。每次BAL后，我们进行了蛋白质测量，细胞用May - Grünwald - Giemsa方法染色，玻片用偏振光研究。通过高效液相色谱法测量丙二醛（MDA）。通过免疫激活（IMAC）技术进行PMN弹性蛋白酶测定。使用荧光底物Z - Phe - Arg - AMC、特异性抑制剂E64和AMC作为内标，采用自动动力学方法测量组织蛋白酶B和L。对BAL样品进行定量斑点印迹后，进行α(1)-抗胰蛋白酶（α(1)AT）的免疫检测。通过与猪胰弹性蛋白酶的酶促反应测定α(1)AT的抑制能力。我们观察到，用Fe2O3（123%）、BaP（31%）和Fe2O3 + BaP（56%）中毒的大鼠MDA水平升高。PMN弹性蛋白酶以及组织蛋白酶B和L的水平升高：Fe2O3（51 - 58%），BaP（52 - 27%）。用Fe2O3 + BaP中毒的大鼠未出现这种效应。三种毒物（Fe2O3：44% - BaP：42% - Fe2O3：41%）使游离α(1)AT降低。在滴注毒物的大鼠组中，α(1)AT的抑制能力较低。
