Evidence for a distinct H7-resistant form of protein kinase C in rat anterior pituitary gland.
Inhibition of phorbol 12,13-dibutyrate-induced protein kinase C (PKC) activity from rat midbrain, anterior pituitary and a number of other tissues, as well as COS 7 cells, was studied in vitro. In anterior pituitary, Ca(2+)-independent activity was notably resistant to H7 but sensitive to staurosporine and Ro 31-8220. All Ca(2+)-dependent activity was sensitive to these three inhibitors. Mezerein and 1,2-dioctanoyl-sn-glycerol also activated this H7-insensitive PKC from anterior pituitary. The distribution of this activity, prominently expressed in pituitary and perhaps also lung, and its characteristic resistance to H7 but not other inhibitors, does not obviously correlate with that of any of the well-characterised PKCs, and may reflect either a novel or a modified isoform.
Ison
A J
AJ
MRC Brain Metabolism Unit, University Department of Pharmacology, Edinburgh, UK.
MacEwan
D J
DJ
Johnson
M S
MS
Clegg
R A
RA
Connor
K
K
Mitchell
R
R
D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D000470:Alkaloids / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000494:pharmacology; D004075:Diglycerides / Q000494:pharmacology; D004224:Diterpenes; D004351:Drug Resistance; D004789:Enzyme Activation / Q000187:drug effects; D007211:Indoles / Q000494:pharmacology; D007546:Isoquinolines / Q000494:pharmacology*; D008168:Lung / Q000201:enzymology; D008297:Male; D015240:Phorbol 12,13-Dibutyrate / Q000494:pharmacology; D010879:Piperazines / Q000494:pharmacology*; D010903:Pituitary Gland, Anterior / Q000201:enzymology*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors*; D051381:Rats; D017208:Rats, Wistar; D019311:Staurosporine; D013729:Terpenes / Q000494:pharmacology
D000470:Alkaloids; D004075:Diglycerides; D004224:Diterpenes; D007211:Indoles; D007546:Isoquinolines; D010879:Piperazines; D013729:Terpenes; C044295:1,2-dioctanoylglycerol; C011309:mezerein; D015240:Phorbol 12,13-Dibutyrate; D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D011493:Protein Kinase C; D019311:Staurosporine; D002118:Calcium; C064758:Ro 31-8220