1. Mechanism of action of the calcium-sensing receptor in human antral gastrin cells 
Alison M.J. Buchan, Paul E. Squires, Mark Ring, R.Mark Meloche 
Gastroenterology 
Volume 120, Issue 5, Pages (April 2001)
DOI: /gast
Copyright © 2001 American Gastroenterological Association Terms and Conditions

2. Fig. 1
(A) Increasing extracellular calcium levels results in a significant increase in gastrin release at concentrations > 1 mmol/L (*P < 0.05 vs. 0.5 mmol/L calcium). Addition of 1 μmol/L U73122 before increasing extracellular calcium significantly inhibited the resultant gastrin release at the higher concentrations of calcium. #P < 0.05 vs. equivalent concentration of calcium alone. Note that at 3.5 mmol/L calcium, U73122 failed to return calcium-stimulated gastrin release to basal levels. (B) Mean (±SEM) basal to peak changes in [Ca2+]i over a range of extracellular Ca2+ concentrations. Data are from 3 separate antral cell preparations, in which the effects of extracellular Ca2+ were examined over the full range of concentrations.
Gastroenterology  , DOI: ( /gast )
Copyright © 2001 American Gastroenterological Association Terms and Conditions

3. Fig. 2
Addition of PKC inhibitors before increasing [Ca2+]i resulted in a significant increase in calcium-stimulated gastrin release. *P < 0.05 compared with corresponding calcium concentration alone. (B) Infusion of bisindolylmaleimide-1 (GF) during the plateau phase of the [Ca2+ ]i response resulted in decreased calcium influx. (A) Mean (±SEM) basal to peak 3.6 mmol/L Ca2+-induced changes in [Ca2+]i recorded before, during, and immediately after addition of bisindolylmaleimide-1 (10 μmol/L). Data are from 2 separate antral cell preparations. **P < 0.01.
Gastroenterology  , DOI: ( /gast )
Copyright © 2001 American Gastroenterological Association Terms and Conditions

4. Fig. 3
(A) Addition of the NSCC blocker DPC resulted in a significant increase in calcium-stimulated gastrin release at all concentration tested. *P < However, addition of the chloride channel/exchanger blocker DIDS had no effect on calcium-stimulated gastrin release. (B) Parallel experiments quantified the ability of DPC to inhibit calcium influx. Note the significant inhibition of the plateau phase of the response. (C) Mean (±SEM) basal to peak 3.6 mmol/L Ca2+–induced changes in [Ca2+]i recorded before, during, and immediately after addition of 350 μmol/L DPC. Data are from 3 separate antral cell preparations. **P < 0.01.
Gastroenterology  , DOI: ( /gast )
Copyright © 2001 American Gastroenterological Association Terms and Conditions

5. Fig. 4
Addition of 1 mmol/L caffeine resulted in a significant increase in calcium-stimulated gastrin release at all concentrations tested. *P < 0.05 compared with the corresponding calcium concentration alone. Preincubation of cells with 1 μmol/L nitrendipine before increasing extracellular calcium levels reversed the effect of caffeine #P < 0.05 compared with the corresponding calcium + caffeine concentration.
Gastroenterology  , DOI: ( /gast )
Copyright © 2001 American Gastroenterological Association Terms and Conditions

6. Fig. 5
Preincubation with 1 μmol/L nitrendipine before addition of DPC reversed the ability of DPC to increase calcium-stimulated gastrin release. #P <0.05 compared with the corresponding calcium concentration in the presence of DPC.
Gastroenterology  , DOI: ( /gast )
Copyright © 2001 American Gastroenterological Association Terms and Conditions

7. Fig. 6
Addition of 100 μmol/L IBMX increased calcium-stimulated gastrin release at all concentrations tested to a level similar to that seen with caffeine and DPC. *P < 0.05 compared with the corresponding calcium concentration alone. Preincubation with 1 μmol/L nitrendipine reversed this effect. #P < 0.05 compared with the presence of calcium and IBMX.
Gastroenterology  , DOI: ( /gast )
Copyright © 2001 American Gastroenterological Association Terms and Conditions

8. Fig. 7
Preincubation of cells with 1 μmol/L nitrendipine reversed the ability of the PKC inhibitor bisindolylmaleimide-1 to increase calcium-stimulated gastrin release. #P < 0.05 compared with the corresponding calcium concentration in the presence of bisindolylmaleimide-1.
Gastroenterology  , DOI: ( /gast )
Copyright © 2001 American Gastroenterological Association Terms and Conditions