Abstract
Aim:
To characterize Ca2+-stimulated exocytosis in isolated mouse pancreatic β cells.
Methods:
An improved method was described for isolation of mouse pancreatic β cells by collagenase P. The Ca2+ channel current and the membrane capacitance were examined by using the whole-cell patch clamp recording technique.
Results:
Using depolarization and flash photolysis of caged Ca2+ to induce Ca2+-dependent exocytosis in β cell from KM mouse, we have explored the characteristics of the Ca2+ channel current and the relationship between Ca2+ signals and exocytosis. The averaged peak Ca2+ current measured at +20 mV was -60±6 pA (n=13).
Conclusion:
We characterized three kinetically different pools of vesicles in mouse pancreatic β cells, namely an immediately releasable pool, a readily releasable pool, and a reserve pool.
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Eliasson L, Renstrom E, Ding WG, Proks P, Rorsman P . Rapid ATP-dependent priming of secretory granules precedes Ca2+-induced exocytosis in mouse pancreatic β-cells. J Physiol 1997; 503: 399–412.
MacDonald PE, Rorsman P . Oscillations, intercellular coupling, and insulin secretion in pancreatic beta cells. PLoS Biol 2006; 4: 49.
Wan QF, Dong Y, Yang H, Lou X, Ding J, Xu T . Protein kinase activation increases insulin secretion by sensitizing the secretory machinery to Ca2+. J Gen Physiol 2004; 124: 653–62.
Chen L, Koh DS, Hille B . Dynamics of calcium clearance in mouse pancreatic beta-cells. Diabetes 2003; 52: 1723–31.
Rorsman P, Trube G . Calcium and delayed potassium currents in mouse pancreatic beta-cells under voltage-clamp conditions. J Physiol 1986; 374: 531–50.
Sorensen JB . Formation, stabilisation and fusion of the readily releasable pool of secretory vesicles. Pflugers Arch 2004; 448: 347–62.
Neher E . Vesicle pools and Ca2+ microdomains: new tools for understanding their roles in neurotransmitter release. Neuron 1998; 20: 389–99.
Xu T, Binz T, Niemann H, Neher E . Multiple kinetic components of exocytosis distinguished by neurotoxin sensitivity. Nat Neurosci 1998; 1: 192–200.
Gopel S, Zhang Q, Eliasson L, Ma XS, Galvanovskis J, Rorsman P, et al. Capacitance measurements of exocytosis in mouse pancreatic alpha-, beta- and delta-cells within intact islets of Langerhans. J Physiol 2004; 556: 711–26.
Olofsson CS, Gopel SO, Barg S, Galvanovskis J, Rorsman P, Eliasson L, et al. Fast insulin secretion reflects exocytosis of docked granules in mouse pancreatic β-cells. Pflugers Arch 2002; 444: 43–51.
Takahashi N, Kadowaki T, Yazaki Y, Miyashita Y, Kasai H . Multiple exocytotic pathways in pancreatic β cells. J Cell Biol 1997; 138: 55–64.
Ammala C, Eliasson L, Bokvist K, Larsson O, Ashcroft FM, Rorsman P . Exocytosis elicited by action potentials and voltage-clamp calcium currents in individual mouse pancreatic β-cells. J Physiol 1993; 472: 665–88.
Wiser O, Trus M, Hernandez A, Renstrom E, Barg S, Rorsman P, et al. The voltage sensitive L-type Ca2+ channel is functionally coupled to the exocytotic machinery. Proc Natl Acad Sci USA 1999; 96: 245–53.
Bokvist K, Eliasson L, Ammala C, Renstrom E, Rorsman P . Colocalization of L-type Ca2+ channels and insulin-containing secretory granules and its significance for the initiation of exocytosis in mouse pancreatic β-cells. EMBO J 1995; 14: 50–7.
Ammala C, Eliasson L, Bokvist K, Larsson O, Ashcroft FM, Rorsman P . Exocytosis elicited by action potentials and voltage-clamp calcium currents in individual mouse pancreatic β-cells. J Physiol 1993; 472: 665–88.
Harata NC, Choi S, Pyle JL, Aravanis AM, Tsien RW . Frequency-dependent kinetics and prevalence of kiss-and-run and reuse at hippocampal synapses studied with novel quenching methods. Neuron 2006; 49: 243–56.
Heinemann C, Chow RH, Neher E, Zucker RS . Kinetics of the secretory response in bovine chromaffin cells following flash photolysis of caged Ca2+. Biophys J 1994; 67: 2546–57.
Smith C, Neher E . Multiple forms of endocytosis in bovine adrenal chromaffin cells. J Cell Biol 1997; 139: 885–94.
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Project supported by the National Natural Science Foundation of China (30270363, 30470448 and 30130230), and the National High Technology Research and Development Program of China (2004CB720000). The laboratory of Tao Xu is supported by the Partner Group Scheme of the Max Planck Institute for Biophysical Chemistry, Göttingen, and the Sino-German Scientific Center.
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Ge, Q., Dong, Ym., Hu, Zt. et al. Characteristics of Ca2+-exocytosis coupling in isolated mouse pancreatic β cells. Acta Pharmacol Sin 27, 933–938 (2006). https://doi.org/10.1111/j.1745-7254.2006.00398.x
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DOI: https://doi.org/10.1111/j.1745-7254.2006.00398.x