Two types of potassium channel regulated by ATP in pancreatic B cells isolated from a type-2 diabetic human.
Two types of K channel regulated by ATP were observed in pancreatic beta cells from a type-2 diabetic man. One type had a conductance of 67 pS at -70 mV in symmetrical 140 mM KCl and was inhibited by intracellular ATP with a half-maximal concentration of 40 microM. ATP inhibition was antagonised by...
| Main Authors: | , , , , , |
|---|---|
| Format: | Journal article |
| Language: | English |
| Published: |
1993
|
| _version_ | 1797072360175566848 |
|---|---|
| author | Williams, B Smith, P Leow, K Shimizu, S Gray, D Ashcroft, F |
| author_facet | Williams, B Smith, P Leow, K Shimizu, S Gray, D Ashcroft, F |
| author_sort | Williams, B |
| collection | OXFORD |
| description | Two types of K channel regulated by ATP were observed in pancreatic beta cells from a type-2 diabetic man. One type had a conductance of 67 pS at -70 mV in symmetrical 140 mM KCl and was inhibited by intracellular ATP with a half-maximal concentration of 40 microM. ATP inhibition was antagonised by ADP. Tolbutamide inhibited the whole-cell K currents half-maximally at 25 microM. This channel has properties similar to those found for the ATP-sensitive K channel in rodent and normal human beta cells. The second channel type observed was an ATP-activated K channel. It had a conductance of 37 pS at -70 mV in symmetrical 140 mM KCl and was activated half-maximally by 9 microM intracellular ATP. This channel was unaffected by 1 mM tolbutamide. In cell-attached patches, one beta cell out of four tested responded to 20 mM glucose with depolarization. The role of the ATP-activated K channel with respect to the (patho)physiology of the beta cell is uncertain. |
| first_indexed | 2024-03-06T23:06:41Z |
| format | Journal article |
| id | oxford-uuid:640e651b-fde3-4a02-981e-df8287c91b73 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-06T23:06:41Z |
| publishDate | 1993 |
| record_format | dspace |
| spelling | oxford-uuid:640e651b-fde3-4a02-981e-df8287c91b732022-03-26T18:16:40ZTwo types of potassium channel regulated by ATP in pancreatic B cells isolated from a type-2 diabetic human.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:640e651b-fde3-4a02-981e-df8287c91b73EnglishSymplectic Elements at Oxford1993Williams, BSmith, PLeow, KShimizu, SGray, DAshcroft, FTwo types of K channel regulated by ATP were observed in pancreatic beta cells from a type-2 diabetic man. One type had a conductance of 67 pS at -70 mV in symmetrical 140 mM KCl and was inhibited by intracellular ATP with a half-maximal concentration of 40 microM. ATP inhibition was antagonised by ADP. Tolbutamide inhibited the whole-cell K currents half-maximally at 25 microM. This channel has properties similar to those found for the ATP-sensitive K channel in rodent and normal human beta cells. The second channel type observed was an ATP-activated K channel. It had a conductance of 37 pS at -70 mV in symmetrical 140 mM KCl and was activated half-maximally by 9 microM intracellular ATP. This channel was unaffected by 1 mM tolbutamide. In cell-attached patches, one beta cell out of four tested responded to 20 mM glucose with depolarization. The role of the ATP-activated K channel with respect to the (patho)physiology of the beta cell is uncertain. |
| spellingShingle | Williams, B Smith, P Leow, K Shimizu, S Gray, D Ashcroft, F Two types of potassium channel regulated by ATP in pancreatic B cells isolated from a type-2 diabetic human. |
| title | Two types of potassium channel regulated by ATP in pancreatic B cells isolated from a type-2 diabetic human. |
| title_full | Two types of potassium channel regulated by ATP in pancreatic B cells isolated from a type-2 diabetic human. |
| title_fullStr | Two types of potassium channel regulated by ATP in pancreatic B cells isolated from a type-2 diabetic human. |
| title_full_unstemmed | Two types of potassium channel regulated by ATP in pancreatic B cells isolated from a type-2 diabetic human. |
| title_short | Two types of potassium channel regulated by ATP in pancreatic B cells isolated from a type-2 diabetic human. |
| title_sort | two types of potassium channel regulated by atp in pancreatic b cells isolated from a type 2 diabetic human |
| work_keys_str_mv | AT williamsb twotypesofpotassiumchannelregulatedbyatpinpancreaticbcellsisolatedfromatype2diabetichuman AT smithp twotypesofpotassiumchannelregulatedbyatpinpancreaticbcellsisolatedfromatype2diabetichuman AT leowk twotypesofpotassiumchannelregulatedbyatpinpancreaticbcellsisolatedfromatype2diabetichuman AT shimizus twotypesofpotassiumchannelregulatedbyatpinpancreaticbcellsisolatedfromatype2diabetichuman AT grayd twotypesofpotassiumchannelregulatedbyatpinpancreaticbcellsisolatedfromatype2diabetichuman AT ashcroftf twotypesofpotassiumchannelregulatedbyatpinpancreaticbcellsisolatedfromatype2diabetichuman |