PKC activators stimulate H+ conductance in chicken enterocytes

Area of Science:

• Cellular Physiology
• Molecular Biology
• Gastrointestinal Physiology

Background:

• Chicken enterocytes possess a proton (H+) conducting pathway crucial for restoring intracellular pH (pHi) after acid exposure.
• Understanding the regulation of this pathway is vital for comprehending cellular acid-base homeostasis.

Purpose of the Study:

• To investigate the role of protein kinase C (PKC) in modulating the H+-conducting pathway in chicken enterocytes.
• To determine if PKC activators influence the rate of proton efflux and intracellular pH recovery.

Main Methods:

• Utilized PKC activators like 1,2-dioctanoyl-rac-glycerol (DOG) and phorbol 12-myristate 13-acetate (PMA) to treat chicken enterocytes.
• Measured the rate of proton efflux and its dependence on pH.
• Employed inhibitors like staurosporine and Zn2+ to confirm PKC involvement.

Main Results:

• PKC activators (DOG, PMA) significantly increased the rate of proton efflux.
• The effect of DOG was dose-dependent, with maximal stimulation observed.
• Staurosporine and Zn2+ inhibited the DOG-induced increase in proton efflux, confirming PKC mediation.
• DOG altered the pH-dependent relationship of proton efflux, shifting it upward and to the right.

Conclusions:

• Protein kinase C (PKC) plays a regulatory role in the proton-conducting pathway of chicken enterocytes.
• PKC activation enhances proton efflux, contributing to intracellular pH recovery from acid loads.
• This finding elucidates a key mechanism in cellular acid-base balance within the gastrointestinal tract.