ATP modulation of large conductance Ca(2+)-activated K(+) channels via a functionally associated protein kinase A in CA1 pyramidal neurons from rat hippocampus.
Using inside-out configuration of patch clamp techniques, ATP modulation of BK(Ca) channels was studied in hippocampal CA1 pyramidal neurons of adult rat. Intracellular ATP application markedly increased BK(Ca) channel activity, and this ATP-produced increase in BK(Ca) channel activity was characterized by a higher opening frequency with no changes in channel open times. In the presence of specific inhibitor against protein kinase A, H-89, ATP did not induce any increase in the channel activity. Furthermore, adding H-89 after addition of ATP reversed the modulation produced by ATP. In contrast, protein kinase C inhibitor chelerythrine exerted no apparent effects on ATP-induced channel activation. The present study suggests that BK(Ca) channels from hippocampal CA1 pyramidal neurons could be modulated by ATP via a functionally associated protein kinase A-like protein.
Gong
Liang W
LW
Department of Physiology, The First Military Medical University, 510515, Guangzhou, PR China.
Gao
Tian M
TM
Huang
Hao
H
Zhou
Ke-Xiong
KX
Tong
Zhenqing
Z
D000255:Adenosine Triphosphate / Q000172:deficiency* / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000378:metabolism / Q000494:pharmacology; D020013:Calcium Signaling / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects / Q000201:enzymology*; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D024681:Potassium Channels, Calcium-Activated / Q000187:drug effects / Q000378:metabolism*; D017966:Pyramidal Cells / Q000187:drug effects / Q000201:enzymology*; D051381:Rats; D017208:Rats, Wistar
D004791:Enzyme Inhibitors; D024681:Potassium Channels, Calcium-Activated; D000255:Adenosine Triphosphate; D017868:Cyclic AMP-Dependent Protein Kinases; D002118:Calcium