Gastric mucin is a large glycoprotein which is thought to play a major role in the protection of the gastrointestinal tract from acid, proteases, pathogenic microorganisms, and mechanical trauma. In Vitro: Gastric mucin may be integrally involved in the mechanism of gastric mucosal injury caused by Helicobacter pylori leading to gastritis, peptic ulceration, and possibly gastric cancer^[1]. Gastric mucins are classified into two types based on their histochemical properties. The first is a surface mucous cell-type mucin, secreted from the surface mucous cells. The second is found in deeper portions of the mucosa and is secreted by gland mucous cells, including mucous neck cells, cardiac gland cells, and pyloric gland cells. The unique O-glycans in gastric mucin appears to function as a natural antibiotic, protecting the host from H. pylori infection^[2]. Gastric mucin may provide protection to the surface epithelium gastrointestinal tract by scavenging oxidants produced within the lumen; however, it does so at the expense of its viscoelastic properties. Both native and pronase-treated mucin effectively scavenge hydroxyl radical and that the scavenging properties are not significantly different. The effective concentration of mucin required for a 50% reduction in malondialdehyde production is 10 mg/mL for both native and pronase-treated mucin^[3].

Gastric mucin 可能參與了幽門螺桿菌引起的胃黏膜損傷導(dǎo)致胃炎、消化性潰瘍甚至胃癌的機(jī)制^[1]。Gastric mucin 根據(jù)其組織化學(xué)特性分為兩類。第一種是表面粘液細(xì)胞型粘蛋白，由表面粘液細(xì)胞分泌。第二種存在于粘膜的較深部分，由腺體粘液細(xì)胞分泌，包括頸粘液細(xì)胞、心肌腺細(xì)胞和幽門腺細(xì)胞。Gastric mucin 中獨(dú)特的 O-聚糖起到天然抗生素的作用，保護(hù)宿主免受 H. pylori 感染^[2]。Gastric mucin 可以通過清除管腔內(nèi)產(chǎn)生的氧化劑來保護(hù)胃腸道表面上皮細(xì)胞；然而，這樣做是以犧牲其粘彈性為代價(jià)的。天然的和經(jīng)鏈霉蛋白酶處理的粘蛋白均能有效清除羥基自由基，并且清除特性沒有顯著差異。對于天然粘蛋白和鏈霉蛋白酶處理的粘蛋白，丙二醛產(chǎn)量減少 50% 所需的粘蛋白有效濃度為 10 mg/mL^[3]。

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

84082-64-4

固體

Off-white to light yellow

胃膜素；胃黏膜素

Room temperature in continental US; may vary elsewhere.

• [1]. Toribara NW, et al. Human gastric mucin. Identification of a unique species by expression cloning. J Biol Chem. 1993 Mar 15;268(8):5879-85.  [Content Brief]

  [2]. Kawakubo M, et al. Natural antibiotic function of a human gastric mucin against Helicobacter pyloriinfection. Science. 2004 Aug 13;305(5686):1003-6.  [Content Brief]

  [3]. Grisham MB, et al. Interaction between oxygen radicals and gastric mucin. Am J Physiol. 1987 Jul;253(1 Pt 1):G93-6.  [Content Brief]