Figure 7.

Effects of protein kinase C (PKC) inhibitors and activators on the response of the rapid component of I_K (I_Kr) to angiotensin II (Ang II; 100 nM). (a and b) Effects of (a) the nonspecific PKC inhibitor, staurosporin (Stau; 100 nM) and (b) the specific PKC inhibitor, Bis-1 (300 nM), on the inhibition of I_Kr tail current by Ang II. (c) A summary of the data expressed as a percentage of decrease of I_Kr tail current by Ang II in the presence of Stau or Bis-1. (d and e) Effects of the PKC activators (d) PMA (100 nM) and (e) PdBu (100 nM), on the inhibition of I_Kr tail current by Ang II. (f) A summary of the data expressed as a percentage of decrease of I_Kr tail current by Ang II in the presence of PMA or PdBu. The amplitude of the I_Kr tail currents was measured using the same pulse protocol described in Figure 5. I_K, the delayed rectifier K⁺ currents.