Potent and selective activation of the pancreatic beta-cell type K(ATP) channel by two novel diazoxide analogues.

AIMS/HYPOTHESIS: We investigated the pharmacological properties of two novel ATP sensitive potassium (K(ATP)) channel openers, 6-Chloro-3-isopropylamino-4 H-thieno[3,2- e]-1,2,4-thiadiazine 1,1-dioxide (NNC 55-0118) and 6-chloro-3-(1-methylcyclopropyl)amino-4 H-thieno[3,2-e]-1,2,4-thiadiazine 1,1-di...

Full description

Bibliographic Details
Main Authors: Dabrowski, M, Larsen, T, Ashcroft, F, Bondo Hansen, J, Wahl, P
Format: Journal article
Language:English
Published: 2003
_version_ 1797057084796174336
author Dabrowski, M
Larsen, T
Ashcroft, F
Bondo Hansen, J
Wahl, P
author_facet Dabrowski, M
Larsen, T
Ashcroft, F
Bondo Hansen, J
Wahl, P
author_sort Dabrowski, M
collection OXFORD
description AIMS/HYPOTHESIS: We investigated the pharmacological properties of two novel ATP sensitive potassium (K(ATP)) channel openers, 6-Chloro-3-isopropylamino-4 H-thieno[3,2- e]-1,2,4-thiadiazine 1,1-dioxide (NNC 55-0118) and 6-chloro-3-(1-methylcyclopropyl)amino-4 H-thieno[3,2-e]-1,2,4-thiadiazine 1,1-dioxide (NN414), on the cloned cardiac (Kir6.2/SUR2A), smooth muscle (Kir6.2/SUR2B) and pancreatic beta cell (Kir6.2/SUR1) types of K(ATP) channel. METHODS: We studied the effects of these compounds on whole-cell currents through cloned K(ATP) channels expressed in Xenopus oocytes or mammalian cells (HEK293). We also used inside-out macropatches excised from Xenopus oocytes. RESULTS: In HEK 293 cells, NNC 55-0118 and NN414 activated Kir6.2/SUR1 currents with EC(50) values of 0.33 micromol/l and 0.45 micromol/l, respectively, compared with that of 31 micro mol/l for diazoxide. Neither compound activated Kir6.2/SUR2A or Kir6.2/SUR2B channels expressed in oocytes, nor did they activate Kir6.2 expressed in the absence of SUR. Current activation was dependent on the presence of intracellular MgATP, but was not supported by MgADP. CONCLUSION/INTERPRETATION: Both NNC 55-0118 and NN414 selectively stimulate the pancreatic beta-cell type of K(ATP) channel with a higher potency than diazoxide, by interaction with the SUR1 subunit. The high selectivity and efficacy of the compounds could prove useful for treatment of disease states where inhibition of insulin secretion is beneficial.
first_indexed 2024-03-06T19:31:15Z
format Journal article
id oxford-uuid:1d88a04b-75b5-4001-8d32-6f350bbd78b6
institution University of Oxford
language English
last_indexed 2024-03-06T19:31:15Z
publishDate 2003
record_format dspace
spelling oxford-uuid:1d88a04b-75b5-4001-8d32-6f350bbd78b62022-03-26T11:11:25ZPotent and selective activation of the pancreatic beta-cell type K(ATP) channel by two novel diazoxide analogues.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:1d88a04b-75b5-4001-8d32-6f350bbd78b6EnglishSymplectic Elements at Oxford2003Dabrowski, MLarsen, TAshcroft, FBondo Hansen, JWahl, PAIMS/HYPOTHESIS: We investigated the pharmacological properties of two novel ATP sensitive potassium (K(ATP)) channel openers, 6-Chloro-3-isopropylamino-4 H-thieno[3,2- e]-1,2,4-thiadiazine 1,1-dioxide (NNC 55-0118) and 6-chloro-3-(1-methylcyclopropyl)amino-4 H-thieno[3,2-e]-1,2,4-thiadiazine 1,1-dioxide (NN414), on the cloned cardiac (Kir6.2/SUR2A), smooth muscle (Kir6.2/SUR2B) and pancreatic beta cell (Kir6.2/SUR1) types of K(ATP) channel. METHODS: We studied the effects of these compounds on whole-cell currents through cloned K(ATP) channels expressed in Xenopus oocytes or mammalian cells (HEK293). We also used inside-out macropatches excised from Xenopus oocytes. RESULTS: In HEK 293 cells, NNC 55-0118 and NN414 activated Kir6.2/SUR1 currents with EC(50) values of 0.33 micromol/l and 0.45 micromol/l, respectively, compared with that of 31 micro mol/l for diazoxide. Neither compound activated Kir6.2/SUR2A or Kir6.2/SUR2B channels expressed in oocytes, nor did they activate Kir6.2 expressed in the absence of SUR. Current activation was dependent on the presence of intracellular MgATP, but was not supported by MgADP. CONCLUSION/INTERPRETATION: Both NNC 55-0118 and NN414 selectively stimulate the pancreatic beta-cell type of K(ATP) channel with a higher potency than diazoxide, by interaction with the SUR1 subunit. The high selectivity and efficacy of the compounds could prove useful for treatment of disease states where inhibition of insulin secretion is beneficial.
spellingShingle Dabrowski, M
Larsen, T
Ashcroft, F
Bondo Hansen, J
Wahl, P
Potent and selective activation of the pancreatic beta-cell type K(ATP) channel by two novel diazoxide analogues.
title Potent and selective activation of the pancreatic beta-cell type K(ATP) channel by two novel diazoxide analogues.
title_full Potent and selective activation of the pancreatic beta-cell type K(ATP) channel by two novel diazoxide analogues.
title_fullStr Potent and selective activation of the pancreatic beta-cell type K(ATP) channel by two novel diazoxide analogues.
title_full_unstemmed Potent and selective activation of the pancreatic beta-cell type K(ATP) channel by two novel diazoxide analogues.
title_short Potent and selective activation of the pancreatic beta-cell type K(ATP) channel by two novel diazoxide analogues.
title_sort potent and selective activation of the pancreatic beta cell type k atp channel by two novel diazoxide analogues
work_keys_str_mv AT dabrowskim potentandselectiveactivationofthepancreaticbetacelltypekatpchannelbytwonoveldiazoxideanalogues
AT larsent potentandselectiveactivationofthepancreaticbetacelltypekatpchannelbytwonoveldiazoxideanalogues
AT ashcroftf potentandselectiveactivationofthepancreaticbetacelltypekatpchannelbytwonoveldiazoxideanalogues
AT bondohansenj potentandselectiveactivationofthepancreaticbetacelltypekatpchannelbytwonoveldiazoxideanalogues
AT wahlp potentandselectiveactivationofthepancreaticbetacelltypekatpchannelbytwonoveldiazoxideanalogues