Role of protein kinase C in cholinergic stimulation of lacrimal gland protein secretion.
The purpose of this study was to determine the role of protein kinase C (PKC) isozymes in carbachol-induced protein secretion in the lacrimal gland. Three isoforms of PKC are present in rat lacrimal gland; PKC-alpha, -delta and -epsilon. Carbachol translocated PKC-epsilon during 5 s incubation. Pretreatment with PdBu for 0 to 4 h down-regulated PKC-alpha by 31% at 20 min, PKC-epsilon by 36% at 2 h, and PKC-delta by 37% at 4 h. A 2 h phorbol ester treatment inhibited carbachol-induced secretion completely at 1 min and partially at 5, and 20 min, but did not alter the carbachol-induced increase in the intracellular [Ca2+]. We conclude that PKC-alpha and -epsilon, but not PKC-delta, are implicated in cholinergic agonist-induced protein secretion in rat lacrimal gland.
Zoukhri
D
D
Schepens Eye Research Institute, Boston, MA 02114.
Hodges
R R
RR
Dicker
D M
DM
Dartt
D A
DA
D000595:Amino Acid Sequence; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002217:Carbachol / Q000494:pharmacology; D007527:Isoenzymes / Q000378:metabolism*; D007765:Lacrimal Apparatus / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D008969:Molecular Sequence Data; D010277:Parasympathomimetics / Q000494:pharmacology*; D010544:Peroxidases / Q000378:metabolism; D015240:Phorbol 12,13-Dibutyrate / Q000494:pharmacology; D011493:Protein Kinase C / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
D007527:Isoenzymes; D010277:Parasympathomimetics; D011506:Proteins; D015240:Phorbol 12,13-Dibutyrate; D002217:Carbachol; D010544:Peroxidases; D011493:Protein Kinase C; D002118:Calcium