To develop techniques for studying transport properties and secretory function of selected cell types in the gastric mucosa, separated fractions of dispersed canine fundic mucosal cells were placed in short-term culture to form epithelial monolayers. Cell fractions enriched in either chief, parietal, or mucous cells were prepared by using counterflow centrifugation and were plated on type I collagen. An epithelial monolayer formed by ≃36 hr. Immunofluorescence with an antipepsinogen I antibody revealed pepsinogen-containing granules in >95% of the cells, regardless of whether the monolayers were formed from the mucous, chief, or parietal cell-enriched fractions. Upon achieving confluency, chief cell monolayers were mounted in Ussing chambers to study their electrical properties. Under basal conditions, monolayers (n=6) had a spontaneous potential difference (PD)(±SEM) of 26 ± 4 mV (apical surface negative), a short-circuit current (I(sc)) (±SEM) of 16 ± 2 μA/cm 2, and a transepithelial resistance (R)(±SEM) of 1,480 ± 210 Ω x cm 2. Histamine increased the short-circuit current, an effect blocked by an H 2-receptor antagonist. Seventy percent of the spontaneous PD was amiloride sensitive, suggesting sodium absorption accounted for a major component of the PD. These preparative techniques yield highly enriched chief cell monolayers, which maintain morphological and functional cellular differentiation for >48 hr in culture, thus allowing study of oriented functions of a selected cell type. The present studies indicate that an H 2 receptor enhances electrogenic ion transport in chief cell monolayers, indicating that histamine can act on fundic mucosal cells other than just parietal cells.
|Number of pages||5|
|Journal||Proceedings of the National Academy of Sciences of the United States of America|
|Issue number||22 I|
|State||Published - 1982|