Membrane capacitance increases induced by histamine and cyclic AMP in single gastric acid-secreting cells of the guinea pig.
During acid secretion, gastric parietal cells undergo profound morphological changes including formation of the apical secretory membrane. To examine the mechanism of histamine-induced increases in the apical membrane area at the single cell level, we monitored the membrane capacitance by applying a time-resolved phase-sensitive detection method to singly isolated parietal cells of guinea pig. A real-time increase in the membrane capacitance was detected within several min after stimulation with histamine. An H2-blocker (cimetidine), but not an H1-blocker (pyrilamine), inhibited the histamine response. Dibutyryl cyclic AMP mimicked the histamine effect. The capacitance response to histamine was sensitive to cytosolic Ca2+, temperature and N-ethylmaleimide. The histamine response was inhibited by intracellular application of a non-hydrolyzable ATP analog (AMP-PNP) and an isoquinolinesulfonamide derivative that works as an inhibitor of protein kinase A (H-8). These results indicate that in parietal cells, elevation of intracellular cyclic AMP induces exocytotic insertion of intracellular membranes into the plasma membrane, presumably by activating protein kinase A.
Hashimoto
A
A
Department of Physiology, Kyoto University Faculty of Medicine, Japan.
Hazama
A
A
Kotera
T
T
Ueda
S
S
Okada
Y
Y
D000818:Animals; D003994:Bucladesine / Q000494:pharmacology; D002469:Cell Separation; D000242:Cyclic AMP / Q000494:pharmacology*; D004594:Electrophysiology; D006168:Guinea Pigs; D006632:Histamine / Q000494:pharmacology*; D007546:Isoquinolines / Q000494:pharmacology; D010295:Parietal Cells, Gastric / Q000187:drug effects / Q000502:physiology*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors
D007546:Isoquinolines; D003994:Bucladesine; D006632:Histamine; C053177:N-(2-(methylamino)ethyl)-5-isoquinolinesulfonamide; D000242:Cyclic AMP; D011493:Protein Kinase C