Bengtsson U, Knutson T W, Knutson L, Dannaeus A, Hällgren R, Ahlstedt S
Allergy Centre, Sahlgrenska University Hospital, Göteborg, Sweden.
Clin Exp Allergy. 1996 Jan;26(1):96-103. doi: 10.1111/j.1365-2222.1996.tb00061.x.
The mechanisms for adverse reactions to foods in the gastrointestinal tract are poorly understood. Presently, only limited possibilities are available for identification of adverse immunological reactions to different foods.
The intestinal inflammatory reactions in adult patients with a history of milk-related gastrointestinal symptoms were studied after intestinal challenges by a jejunal perfusion technique and compared with the reactions in a control group.
Five skin-prick test and radioallergosorbent test negative and lactose tolerant patients with a history of milk-related gastrointestinal symptoms, verified by double-blind placebo-controlled challenge, and eight healthy controls were investigated. Perfusions were performed allowing analyses of a well-defined 'closed' jejunal segment. Milk perfusions were performed in patients and controls after an overnight fast. Ten millilitres of milk were administered to the segment at 3 mL/min. The jejunal fluid levels of hyaluronan (hyaluronic acid) and albumin were measured.
In the five patients the milk challenges induced as a mean fivefold increased levels of hyaluronan compared with prestimulation values, whereas no such increases were seen in the control subjects. Albumin, as a marker of plasma leakage, was also increased in the patients but not in the control subjects.
The underlying mechanisms for locally increased levels of hyaluronan and also albumin in the intestinal lumen may be secretion of lymph rich in hyaluronan and reflect the mucosal oedema. This capacity of the intestinal mucosa to react with lymph leakage towards a locally infused allergen may be a possible way to delineate gastrointestinal reactions in food-related disorders.
胃肠道对食物不良反应的机制尚不清楚。目前,识别对不同食物的不良免疫反应的可能性有限。
采用空肠灌注技术对有牛奶相关胃肠道症状病史的成年患者进行肠道激发试验后,研究其肠道炎症反应,并与对照组的反应进行比较。
研究了5名皮肤点刺试验和放射性变应原吸附试验阴性且乳糖耐受、有牛奶相关胃肠道症状病史(经双盲安慰剂对照激发试验证实)的患者以及8名健康对照者。进行灌注以分析明确界定的“封闭”空肠段。患者和对照者在禁食过夜后进行牛奶灌注。以3 mL/min的速度向该段注入10毫升牛奶。测量空肠液中透明质酸和白蛋白的水平。
与刺激前值相比,5名患者的牛奶激发试验导致透明质酸水平平均升高了五倍,而对照组未出现这种升高。作为血浆渗漏标志物的白蛋白在患者中也有所增加,但在对照者中未增加。
肠腔内透明质酸和白蛋白局部水平升高的潜在机制可能是富含透明质酸的淋巴液分泌,反映了黏膜水肿。肠黏膜对局部注入的变应原产生淋巴渗漏反应的这种能力,可能是界定食物相关疾病中胃肠道反应的一种可能方式。