Abstract
The effect of protein kinase C (PKC) on carbachol (CCh)-activated nonselective cationic current (I CCh) was investigated in guinea-pig gastric myocytes using a PKC activator, phorbol 12, 13 dibutyrate (PDBu). Pretreatment with 1 μ M PDBu suppressed I CCh by 96.5 ± 2.9% (n = 14) in a reversible manner in nystatin-perforated mode. In the presence of 1 μM chelerythrine , a PKC inhibitor, inhibition of I CChby PDBu was not seen. In whole-cell mode, the inhibition of I CCh by PDBu was dependent on intracellular MgATP. In the presence of MgATP in the pipette, PDBu decreased I CCh by 98.8 ± 1.2% (n = 5) as was observed in nystatin-perforated mode. However, PDBu had little effect on I CCh in the absence of MgATP in the pipette; the extent of inhibition was 12.7 ± 4.3% (n = 8). PDBu also suppressed the generation of cationic current induced by intracellularly perfused GTP[γS]. In the PDBu-pretreated group (n = 9) and PDBu-untreated control group (n = 6), GTP[γS]-induced currents were 6.7 ± 2.4 pA and 236 ± 23 pA, respectively. These results suggest that PKC modulates I CCh at postreceptor sites via protein phosphorylation.
Similar content being viewed by others
Author information
Authors and Affiliations
Additional information
Received: 4 April 1997 / Received after revision: 27 June 1997 / Accepted: 3 June 1997
Rights and permissions
About this article
Cite this article
Ahn, S., Kim, S., So, I. et al. Inhibitory effect of phorbol 12, 13 dibutyrate on carbachol-activated nonselective cationic current in guinea-pig gastric myocytes. Pflügers Arch 434, 505–507 (1997). https://doi.org/10.1007/s004240050429
Issue Date:
DOI: https://doi.org/10.1007/s004240050429