Effect of somatostatin and proton pump inhibitor on the siowly-activiting voltage-dependent K+ channel in the rat pancreatic acini
10.3760/cma.j.issn.0254-1432.2011.10.011
- VernacularTitle:生长抑素及质子泵抑制剂对大鼠胰腺腺泡细胞慢活化电压依赖性钾离子通道的影响
- Author:
Jia CAI
;
Wenxiang HUANG
;
Hesheng LUO
- Publication Type:Journal Article
- Keywords:
Pancreas;
Somatostatin;
Omeprazole;
Patch-clamp techniques;
Potassium channels
- From:
Chinese Journal of Digestion
2011;31(10):690-694
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the effect and mechanism of somatostatin and proton pump inhibitor (PPI) on Iks in pancreatic acini (RPA) by testing the change of slowly-activiting voltagedependent K+ channel current (Iks).Methods Pancreatic acini was isolated and its suspension was obtained.Iks values of different groups were recorded by an EPC10 patch clamp amplifier and the difference among the groups was compared.The groups were divided as followed:washing solution treated as control group,5 μmol/L or 20 μmol/L 293B groups,5 nmol/L secretin group,5 nmol/L secretin with somatostatin at 100 nmol/L or 10 nmol/L or 1 nmol/L groups,0.3 nmol/L 8Br-cAMP group,0.3 nmol/L 8Br-cAMP with 100 nmol/L somatostatin group,1 μmol/L acetylcholine group,1μmol/L acetylcholine with 100 nmol/L somatostatin group,5 nmol/L secretin with omeprazole at 10-5 mol/L or 10-6 mol/L or 10-7 mol/L groups,1 μmol/L acetylcholine with omeprazole at 10-5 mol/L or 10-6mol/L or 10-7 mol/L groups.Groups were compared by ANOVA,P ＜ 0.05 was considered statistically significant.Results The resting membrane voltage of rat RPA was - (40 ± 0.8) mV,and when depolarization to +10 mV,Iks of control group was (420.0±3.2) pA.After treated with 5 μmol/L or 20 μmol/L 293B,Iks of RPA decreased to (60.4±4.2)％ and (30.2±3.1)％(F=6.87,P＜0.05) of control group.Stimulated with 5 nmol/L secretin,Iks increased to (823.0±2.2) pA,and after adding somatostatin at 100 nmol/L or 10 nmol/L or 1 nmol/L,Iks decreased to (510.0±3.2) pA,(584.0±2.8) pA and (789.0±6.9) pA respectively(F=5.67,P＜0.05),after adding omeprazole at 10-5mol/L or 10-6mol/L or 107mol/L,the peak of Iks was (806.5±3.6) pA,(814.8±3.2) pA and (816.3±2.9) pA (P＞0.05).After stimulated with 1 μmol/L acetylcholine,the peak value of Iks was (966.0± 3.2) pA,and after adding omeprazole at 10-5 mol/L or 10-6 mol/L or 107mol/L,the peak of Iks was (956.3±10.3) pA,(957.5±8.6) pA and (960.0±8.4) pA (P＞0.05).Conclusion Somatostatin can inhibit Iks opening,and there is no significant inhibition of PPI on this channel.
