Increases in cellular calcium concentration stimulate pepsinogen secretion from dispersed chief cells.
Intracellular calcium concentration ([Ca]i) and pepsinogen secretion from dispersed chief cells from guinea pig stomach were determined before and after stimulation with calcium ionophores. [Ca]i was measured using the fluorescent probe quin2. Basal [Ca]i was 105 +/- 4 nM. Pepsinogen secretion was measured with a new assay using 125I-albumin substrate. This assay is 1000-fold more sensitive than the widely-used spectrophotometric assay, technically easy to perform, rapid, and relatively inexpensive. The kinetics and stoichiometry of ionophore-induced changes in [Ca]i and pepsinogen secretion were similar. These data support a role for calcium as a cellular mediator of pepsinogen secretion.
D000634:Aminoquinolines; D000818:Animals; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000502:physiology*; D003593:Cytoplasm / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004987:Ethers / Q000494:pharmacology; D005753:Gastric Mucosa / Q000166:cytology / Q000378:metabolism*; D006168:Guinea Pigs; D015759:Ionomycin; D008297:Male; D010434:Pepsin A / Q000032:analysis; D010435:Pepsinogens / Q000378:metabolism*
D000634:Aminoquinolines; D004987:Ethers; D010435:Pepsinogens; D000001:Calcimycin; D015759:Ionomycin; C035738:Quin2-acetoxymethyl ester; D010434:Pepsin A; D002118:Calcium