大鼠胃黏膜分离细胞组分中一氧化氮合酶的差异分布。

Differential distribution of nitric oxide synthase between cell fractions isolated from the rat gastric mucosa.

作者信息

Brown J F, Tepperman B L, Hanson P J, Whittle B J, Moncada S

机构信息

Wellcome Research Laboratories, Beckenham, Kent, UK.

出版信息

Biochem Biophys Res Commun. 1992 Apr 30;184(2):680-5. doi: 10.1016/0006-291x(92)90643-y.

DOI:10.1016/0006-291x(92)90643-y

PMID:1374239

Abstract

Cells isolated from the rat gastric mucosa were resolved into two fractions on a percoll density gradient, and into five fractions using counterflow centrifugation (elutriation). Ca(2+)-dependent nitric oxide synthase (NOS) activity was found in the high density percoll fraction but not in the parietal cell enriched low density fraction. This activity was inhibited by NG-monomethyl-L-arginine with an IC50 of 3.7 microM. Cells in the elutriator fraction rich in mucous-epithelial cells exhibited the highest NOS activity, while the smaller cell fractions had no detectable NOS yet had the highest basal release of prostaglandin E2. The parietal cell enriched elutriator fraction again had low NOS activity. The activity of a constitutive NOS in the mucous-cell fraction may indicate a role of NO in the regulation of epithelial cell integrity or secretion.

摘要

从大鼠胃黏膜分离出的细胞在 Percoll 密度梯度上被分离为两个组分，使用逆流离心法（淘析法）则被分离为五个组分。在 Percoll 高密度组分中发现了 Ca(2+) 依赖性一氧化氮合酶（NOS）活性，而在富含壁细胞的低密度组分中未发现该活性。该活性被 NG-单甲基-L-精氨酸抑制，IC50 为 3.7 microM。富含黏液上皮细胞的淘析组分中的细胞表现出最高的 NOS 活性，而较小的细胞组分未检测到 NOS，但前列腺素 E2 的基础释放量最高。富含壁细胞的淘析组分的 NOS 活性再次较低。黏液细胞组分中组成型 NOS 的活性可能表明 NO 在调节上皮细胞完整性或分泌中起作用。