Cytochemistry of protein kinase C and Na-K-ATPase in rabbit ciliary processes treated with phorbol ester.
Immunocytochemical localization of protein kinase C (PKC) in rabbit ciliary processes was investigated using anti-PKC monoclonal antibodies (MAbs) against rabbit Types 1, 2, and 3 PKC. Specific immunolabeling was observed in nonpigmented epithelial (NPE) cells and in the capillaries of the ciliary processes with anti-Types 2 and 3 MAbs. No apparent staining was seen with anti-Type 1 MAbs. Immunoelectron microscopy of Types 2 and 3 MAbs revealed a diffuse distribution of immunoreactive PKC in the cytoplasm, in the nucleus, and on the plasma membrane in the NPE cells. When incubated with phorbol 12-myristate 13-acetate (PMA), the distribution of PKC was basically similar to that of the untreated group. However, the labelling density on the plasma membrane at basolateral interdigitation increased considerably for anti-Types 2 and 3 PKC MAbs. In addition, the enzyme cytochemical activity of Na-K-ATPase (ouabain-sensitive K-NPPase) and its change after PMA administration in the ciliary processes were observed. An intense reaction was seen on the basolateral plasma membrane of the NPE cells. In the PMA-treated group, the enzyme activity of Na-K-ATPase apparently was decreased. These findings provide evidence that PKC plays a crucial role in the function of the NPE cells of the ciliary processes, possibly in aqueous humor production.
Nakano
T
T
Department of Anatomy, Kyoto University Faculty of Medicine, Japan.
Fujimoto
K
K
Honda
Y
Y
Ogawa
K
K
D009597:4-Nitrophenylphosphatase / Q000378:metabolism; D000818:Animals; D002924:Ciliary Body / Q000166:cytology / Q000201:enzymology*; D006651:Histocytochemistry; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D016253:Microscopy, Immunoelectron; D011493:Protein Kinase C / Q000378:metabolism*; D011817:Rabbits; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D014018:Tissue Distribution
D011493:Protein Kinase C; D009597:4-Nitrophenylphosphatase; D000254:Sodium-Potassium-Exchanging ATPase; D013755:Tetradecanoylphorbol Acetate