Kuhn M, Kulaksiz H, Cetin Y, Frank M, Nold R, Arnold R, Böker K, Bischoff S C, Manns M P, Forssmann W G
Lower Saxony Institute for Peptide Research, Hannover, Germany.
Eur J Clin Invest. 1995 Dec;25(12):899-905. doi: 10.1111/j.1365-2362.1995.tb01964.x.
Guanylin is a recently discovered peptide hormone that activates intestinal guanylate cyclase (GC-C) and thereby stimulates intestinal chloride secretion. Immunohistochemistry showed its presence in enterochromaffin (EC) cells of the gut. In vitro studies suggested that guanylin plays an important role in the endogenous modulation of intestinal salt and water secretion. In the present study the concentration of circulating immunoreactive (IR)-guanylin in plasma of patients with intestinal diarrhoea due to chronic bowel inflammation and patients with carcinoid tumours were measured with a specific radioimmunoassay. In 22 patients with Crohn's disease and eight patients with ulcerative colitis, plasma concentrations of IR-guanylin were 44 +/- 3 and 42 +/- 4 fmol mL-1, respectively. Levels were not different from that in 44 healthy volunteers suggesting that the circulating hormone is not involved in diarrhoea of these patients. In 17 patients with symptomatic carcinoid tumors the median concentration of circulating IR-guanylin was significantly enhanced (94 +/- 16 fmol mL-1, range 37-312 fmol mL-1). Immunohistochemistry revealed the presence of immunoreactive guanylin in carcinoid tissues, suggesting that these tumours co-release guanylin along with their usual resident hormone, serotonin. Enhanced local secretion of guanylin may play a causal role in diarrhoea of these patients and its elevation in plasma may be of diagnostic value in this type of endocrine tumours.
鸟苷林是一种最近发现的肽类激素，它可激活肠道鸟苷酸环化酶（GC-C），从而刺激肠道氯化物分泌。免疫组织化学显示其存在于肠道的肠嗜铬（EC）细胞中。体外研究表明，鸟苷林在肠道盐和水分泌的内源性调节中起重要作用。在本研究中，采用特异性放射免疫分析法测定了慢性肠道炎症引起的肠道腹泻患者和类癌肿瘤患者血浆中循环免疫反应性（IR）-鸟苷林的浓度。在22例克罗恩病患者和8例溃疡性结肠炎患者中，IR-鸟苷林的血浆浓度分别为44±3和42±4 fmol/mL。这些水平与44名健康志愿者的水平无差异，表明循环激素与这些患者的腹泻无关。在17例有症状的类癌肿瘤患者中，循环IR-鸟苷林的中位浓度显著升高（94±16 fmol/mL，范围37-312 fmol/mL）。免疫组织化学显示类癌组织中存在免疫反应性鸟苷林，提示这些肿瘤除了释放其通常分泌的激素5-羟色胺外，还共同释放鸟苷林。鸟苷林局部分泌增强可能是这些患者腹泻的原因，其血浆水平升高可能对这类内分泌肿瘤具有诊断价值。
