@article{oai:niigata-u.repo.nii.ac.jp:00025972,
 author = {Satoh, Hiroyasu},
 issue = {2},
 journal = {新潟歯学会雑誌, 新潟歯学会雑誌},
 month = {Dec},
 note = {Efects of phorbol esters (stimulator of protein kinase C) on the L-type Ca^2+ current in isolated single rabbit sino-atrial (SA) nodal cells were examined. In whole-cell voltage-clamp experiments, 12-0-tetradecanoylphorbo1-13-acetate (TPA) at 10^-7 M inhibited the L-type Ca^2+ current. Pretreatment with H-7 (10^-5 M), an antagonist of protein kinase C (PK-C), did not modify the TPA-induced depression. The time course of inactivation process for the L-type Ca^2 current was slowed. In cell-attached patch-clamp experiments, TPA (10^-7 M) profoundly decreased the probability of the opening of unitary L-type Ca^2+ channels (a dihydropyridine-sensitive). The conductance was unaffected (18 ± 1pS, n=5). Even H-7(10^-5 M) alone tended to inhibit the opening of the channels. Addition of TPA (10^-7 M) to the H-7-containing solution caused further decrease in the opening. On the other hand, 4-alpha-phorbol-12, 13-didecanoate (not a PK-C activator) had no effect on the Ca^2+ channels. These results indicate that the PK-C Stimulation decreases the opening of L-type Ca^2+ channels of the SA nodal cell membranes.},
 pages = {21--28},
 title = {Effects of Protein Kinase C on the L-Type Ca2+ Channel in Single Rabbit Sino-Atrial Nodal Cells : Analysis by Patch-Clamp Technique},
 volume = {24},
 year = {1994}
}