Protein phosphatase inhibitors potentiate Ca2+/calmodulin-dependent protein kinase II activity in rat pancreatic acinar cells.
(1996) In Biochemical and Biophysical Research Communications 225(2). p.520-524- Abstract
- Cholecystokinin (CCK) is known to rapidly and transiently increase both [Ca2+]iand autonomous CaM kinase II activity in rat pancreatic acini. Because induction of autonomous activity may involve intramolecular autophosphorylation, the effects of protein phosphatase inhibitors were examined. None of the inhibitors tested (okadaic acid, calyculin A, and cyclosporin A) affected basal activity. Okadaic acid, a potent inhibitor of PP2A and weaker inhibitor of PP1, increased the peak autonomous activity by 30% over the level normally induced by CCK alone, while calyculin A, a potent inhibitor of both PP1 and PP2A, showed an even greater increase of 97%. Both inhibitors also delayed the decline of autonomous activity and calyculin A had a more... (More)
- Cholecystokinin (CCK) is known to rapidly and transiently increase both [Ca2+]iand autonomous CaM kinase II activity in rat pancreatic acini. Because induction of autonomous activity may involve intramolecular autophosphorylation, the effects of protein phosphatase inhibitors were examined. None of the inhibitors tested (okadaic acid, calyculin A, and cyclosporin A) affected basal activity. Okadaic acid, a potent inhibitor of PP2A and weaker inhibitor of PP1, increased the peak autonomous activity by 30% over the level normally induced by CCK alone, while calyculin A, a potent inhibitor of both PP1 and PP2A, showed an even greater increase of 97%. Both inhibitors also delayed the decline of autonomous activity and calyculin A had a more potent effect than okadaic acid. Cyclosporin A, an inhibitor of PP2B, had no effect. The data indicate that PP1 may be involved in the dephosphorylation of CaMK II and decline of autonomous activity. (Less)
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https://lup.lub.lu.se/record/5a367d0a-d134-46b0-9013-f03b01005945
- author
- Hwang, Jason ; Bragado, Julia ; Duan, Rui-Dong LU and Williams, John A
- publishing date
- 1996
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Biochemical and Biophysical Research Communications
- volume
- 225
- issue
- 2
- pages
- 5 pages
- publisher
- Elsevier
- external identifiers
-
- scopus:0030583295
- ISSN
- 1090-2104
- DOI
- 10.1006/bbrc.1996.1205
- language
- English
- LU publication?
- no
- id
- 5a367d0a-d134-46b0-9013-f03b01005945
- date added to LUP
- 2019-02-03 10:52:21
- date last changed
- 2022-01-31 17:21:53
@article{5a367d0a-d134-46b0-9013-f03b01005945, abstract = {{Cholecystokinin (CCK) is known to rapidly and transiently increase both [Ca2+]iand autonomous CaM kinase II activity in rat pancreatic acini. Because induction of autonomous activity may involve intramolecular autophosphorylation, the effects of protein phosphatase inhibitors were examined. None of the inhibitors tested (okadaic acid, calyculin A, and cyclosporin A) affected basal activity. Okadaic acid, a potent inhibitor of PP2A and weaker inhibitor of PP1, increased the peak autonomous activity by 30% over the level normally induced by CCK alone, while calyculin A, a potent inhibitor of both PP1 and PP2A, showed an even greater increase of 97%. Both inhibitors also delayed the decline of autonomous activity and calyculin A had a more potent effect than okadaic acid. Cyclosporin A, an inhibitor of PP2B, had no effect. The data indicate that PP1 may be involved in the dephosphorylation of CaMK II and decline of autonomous activity.}}, author = {{Hwang, Jason and Bragado, Julia and Duan, Rui-Dong and Williams, John A}}, issn = {{1090-2104}}, language = {{eng}}, number = {{2}}, pages = {{520--524}}, publisher = {{Elsevier}}, series = {{Biochemical and Biophysical Research Communications}}, title = {{Protein phosphatase inhibitors potentiate Ca2+/calmodulin-dependent protein kinase II activity in rat pancreatic acinar cells.}}, url = {{http://dx.doi.org/10.1006/bbrc.1996.1205}}, doi = {{10.1006/bbrc.1996.1205}}, volume = {{225}}, year = {{1996}}, }