Glucose-dependent regulation of rhythmic action potential firing in pancreatic beta-cells by K-ATP-channel modulation
(2002) In Journal of Physiology 545(2). p.501-507- Abstract
- The regulation of a K+ current activating during oscillatory electrical activity (I-K,I-slow) in an insulin-releasing,beta-cell was studied by applying the perforated patch whole-cell technique to intact mouse pancreatic islets. The resting whole-cell conductance in the presence of 10 mm glucose amounted to 1.3 nS, which rose by 50% during a series of 26 simulated action potentials. Application of the K-ATP-channel blocker tolbutamide produced uninterrupted action potential firing and reduced IK,slow by similar to50%. Increasing glucose from 15 to 30 mm, which likewise converted oscillatory electrical activity into continuous action potential firing, reduced I-K,I-slow by similar to30% whilst not affecting the resting conductance. Action... (More)
- The regulation of a K+ current activating during oscillatory electrical activity (I-K,I-slow) in an insulin-releasing,beta-cell was studied by applying the perforated patch whole-cell technique to intact mouse pancreatic islets. The resting whole-cell conductance in the presence of 10 mm glucose amounted to 1.3 nS, which rose by 50% during a series of 26 simulated action potentials. Application of the K-ATP-channel blocker tolbutamide produced uninterrupted action potential firing and reduced IK,slow by similar to50%. Increasing glucose from 15 to 30 mm, which likewise converted oscillatory electrical activity into continuous action potential firing, reduced I-K,I-slow by similar to30% whilst not affecting the resting conductance. Action potential firing may culminate in opening of K-ATP channels by activation of ATP-dependent Ca2+ pumping as suggested by the observation that the sarco-endoplasmic reticulum Ca2+-ATPase (SERCA) inhibitor thapsigargin (4 muM) inhibited I-K,I-slow by 25% and abolished bursting electrical activity. We conclude that oscillatory glucose-induced electrical activity in the beta-cell involves the opening of KATP-channel activity and that these channels, in addition to constituting the glucose-regulated K+ conductance, also play a role in the graded response to supra-threshold glucose concentrations. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/320611
- author
- Kanno, T ; Rorsman, Patrik LU and Göpel, Sven LU
- organization
- publishing date
- 2002
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of Physiology
- volume
- 545
- issue
- 2
- pages
- 501 - 507
- publisher
- The Physiological Society
- external identifiers
-
- pmid:12456829
- wos:000180075200018
- scopus:0036905897
- ISSN
- 1469-7793
- DOI
- 10.1113/jphysiol.2002.031344
- language
- English
- LU publication?
- yes
- id
- bac401d5-1fa3-4bae-82e6-296b864b68e2 (old id 320611)
- date added to LUP
- 2016-04-01 17:12:04
- date last changed
- 2022-02-20 19:20:15
@article{bac401d5-1fa3-4bae-82e6-296b864b68e2, abstract = {{The regulation of a K+ current activating during oscillatory electrical activity (I-K,I-slow) in an insulin-releasing,beta-cell was studied by applying the perforated patch whole-cell technique to intact mouse pancreatic islets. The resting whole-cell conductance in the presence of 10 mm glucose amounted to 1.3 nS, which rose by 50% during a series of 26 simulated action potentials. Application of the K-ATP-channel blocker tolbutamide produced uninterrupted action potential firing and reduced IK,slow by similar to50%. Increasing glucose from 15 to 30 mm, which likewise converted oscillatory electrical activity into continuous action potential firing, reduced I-K,I-slow by similar to30% whilst not affecting the resting conductance. Action potential firing may culminate in opening of K-ATP channels by activation of ATP-dependent Ca2+ pumping as suggested by the observation that the sarco-endoplasmic reticulum Ca2+-ATPase (SERCA) inhibitor thapsigargin (4 muM) inhibited I-K,I-slow by 25% and abolished bursting electrical activity. We conclude that oscillatory glucose-induced electrical activity in the beta-cell involves the opening of KATP-channel activity and that these channels, in addition to constituting the glucose-regulated K+ conductance, also play a role in the graded response to supra-threshold glucose concentrations.}}, author = {{Kanno, T and Rorsman, Patrik and Göpel, Sven}}, issn = {{1469-7793}}, language = {{eng}}, number = {{2}}, pages = {{501--507}}, publisher = {{The Physiological Society}}, series = {{Journal of Physiology}}, title = {{Glucose-dependent regulation of rhythmic action potential firing in pancreatic beta-cells by K-ATP-channel modulation}}, url = {{http://dx.doi.org/10.1113/jphysiol.2002.031344}}, doi = {{10.1113/jphysiol.2002.031344}}, volume = {{545}}, year = {{2002}}, }