Perchlorate stimulates insulin secretion by shifting the gating of L-type Ca2+ currents in mouse pancreatic B-cells towards negative potentials
(2001) In Pflügers Archiv 441(5). p.587-595- Abstract
- The effects of the chaotrophic anion perchlorate (ClO4-) on glucose-induced electrical activity, exocytosis and ion channel activity in mouse pancreatic B-cells were investigated by patch-clamp recordings and capacitance measurements. ClO4- stimulated glucose-induced electrical activity and increased the action potential frequency by 70% whilst not affecting the membrane potential when applied in the presence of a subthreshold concentration of the sugar. ClO4- did not influence ATP-dependent K (KATP) channel activity and voltage-gated delayed K+ current. Similarly, ClO4- had no effect on Ca2+-dependent exocytosis. The stimulation of electrical activity and insulin secretion was instead attributable to an enhancement of the whole-cell Ca2+... (More)
- The effects of the chaotrophic anion perchlorate (ClO4-) on glucose-induced electrical activity, exocytosis and ion channel activity in mouse pancreatic B-cells were investigated by patch-clamp recordings and capacitance measurements. ClO4- stimulated glucose-induced electrical activity and increased the action potential frequency by 70% whilst not affecting the membrane potential when applied in the presence of a subthreshold concentration of the sugar. ClO4- did not influence ATP-dependent K (KATP) channel activity and voltage-gated delayed K+ current. Similarly, ClO4- had no effect on Ca2+-dependent exocytosis. The stimulation of electrical activity and insulin secretion was instead attributable to an enhancement of the whole-cell Ca2+ current. This effect was particularly pronounced at voltages around the threshold for action potential initiation and a doubling of the current amplitude was observed at -30 mV. This was due to a 7-mV shift in the gating of the Ca2+ current towards negative voltages. The action of ClO4- was more pronounced when added in the presence of 0.1 mM BAY K8644, whereas no stimulation was observed when applied at a maximal concentration of the agonist (1 mM). Single-channel recordings revealed that the effect of ClO4- on whole-cell currents was principally due to a 60% increase in the mean duration of the long openings and the number of active channels. We propose that ClO4- stimulates insulin secretion and electrical activity by exerting a BAY K8644-like action on Ca2+ channel gating. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1119808
- author
- Larsson-Nyren, Gerd ; Sehlin, Janove ; Rorsman, Patrik LU and Renström, Erik LU
- organization
- publishing date
- 2001
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- B-cell, Ca 2+ -channel, Chaotrophic anion, Insulin
- in
- Pflügers Archiv
- volume
- 441
- issue
- 5
- pages
- 587 - 595
- publisher
- Springer
- external identifiers
-
- pmid:11294239
- scopus:0035112084
- ISSN
- 0031-6768
- DOI
- 10.1007/s004240000426
- language
- English
- LU publication?
- yes
- id
- a825cc4f-506a-491c-b21f-1e63bc982f23 (old id 1119808)
- date added to LUP
- 2016-04-01 16:31:33
- date last changed
- 2022-03-30 08:30:37
@article{a825cc4f-506a-491c-b21f-1e63bc982f23, abstract = {{The effects of the chaotrophic anion perchlorate (ClO4-) on glucose-induced electrical activity, exocytosis and ion channel activity in mouse pancreatic B-cells were investigated by patch-clamp recordings and capacitance measurements. ClO4- stimulated glucose-induced electrical activity and increased the action potential frequency by 70% whilst not affecting the membrane potential when applied in the presence of a subthreshold concentration of the sugar. ClO4- did not influence ATP-dependent K (KATP) channel activity and voltage-gated delayed K+ current. Similarly, ClO4- had no effect on Ca2+-dependent exocytosis. The stimulation of electrical activity and insulin secretion was instead attributable to an enhancement of the whole-cell Ca2+ current. This effect was particularly pronounced at voltages around the threshold for action potential initiation and a doubling of the current amplitude was observed at -30 mV. This was due to a 7-mV shift in the gating of the Ca2+ current towards negative voltages. The action of ClO4- was more pronounced when added in the presence of 0.1 mM BAY K8644, whereas no stimulation was observed when applied at a maximal concentration of the agonist (1 mM). Single-channel recordings revealed that the effect of ClO4- on whole-cell currents was principally due to a 60% increase in the mean duration of the long openings and the number of active channels. We propose that ClO4- stimulates insulin secretion and electrical activity by exerting a BAY K8644-like action on Ca2+ channel gating.}}, author = {{Larsson-Nyren, Gerd and Sehlin, Janove and Rorsman, Patrik and Renström, Erik}}, issn = {{0031-6768}}, keywords = {{B-cell; Ca 2+ -channel; Chaotrophic anion; Insulin}}, language = {{eng}}, number = {{5}}, pages = {{587--595}}, publisher = {{Springer}}, series = {{Pflügers Archiv}}, title = {{Perchlorate stimulates insulin secretion by shifting the gating of L-type Ca2+ currents in mouse pancreatic B-cells towards negative potentials}}, url = {{http://dx.doi.org/10.1007/s004240000426}}, doi = {{10.1007/s004240000426}}, volume = {{441}}, year = {{2001}}, }