TRANSITIONS AND TRANSPORT IN GASTRIC MUCOSA

这项工作的主要目标是确定如何酸分泌 兔胃壁细胞维持离子稳态， 它们的分泌活动有很大的变化。显微荧光光谱法和 pH、Na、Ca、Cl、K敏感荧光的数字图像处理 染料将用于确定离子交换剂（Na/H，Cl/HCO 3， Na/Ca）、协同转运蛋白（Na/HCO 3）、ATP酶（Na/K和H/K）和Ca “通道”由H2激动剂组胺和毒蕈碱控制， 激动剂卡巴胆碱。不同的第二信使如Ca， pH、cAMP和蛋白激酶C可能在刺激分泌偶联中起作用， 还将研究Na/H和Cl/HCO 3交换的作用 可能会起到维持“屏障”功能的作用， 酶分泌主细胞和粘液分泌表面上皮细胞。 这些数据对于了解胃细胞如何在体内运作非常重要。 健康和疾病状态。此外，由于膜运输过程 刺激-分泌偶联机制存在于大多数分泌型 细胞，这项工作应具有相当广泛的相关性。

The major goal of this work is to determine how the acid-secreting parietal cells of the rabbit stomach maintain ionic homeostasis during large changes in their secretory activity. Microspectrofluorimetry and digital image processing of pH-, Na- Ca-, Cl- and K-sensitive fluorescent dyes will be used to determine how the ion exchangers (Na/H, Cl/HCO3, and Na/Ca), cotransporter (Na/HCO3), ATP-ases (Na/K and H/K), and Ca "channels" are controlled by the H2 agonist histamine and muscarinic agonist carbachol. The roles which different second messengers like Ca, pH, CAMP and protein kinase C may play in stimulus secretion coupling will also be investigated, as will the roles which Na/H and Cl/HC03 exchange might play in maintenance of the "barrier" function of the enzyme-secreting chief cells and mucus-secreting surface epithelial cells. These data will be of importance in knowing how stomach cells operate in healthy and diseased states. Also, since the membrane transport processes and stimulus-secretion coupling mechanisms are present in most secretory cells, the work should have quite broad relevance.