Potentiation of cyclic AMP-mediated proopiomelanocortin gene promoter activity by calcium channel blockers in a pituitary cell line

2007 ◽  
Vol 558 (1-3) ◽  
pp. 1-6 ◽  
Author(s):  
Masahiro Ikeda ◽  
Masahiro Kakuyama ◽  
Takehiro Shoda ◽  
Yasumasa Iwasaki ◽  
Kazuhiko Fukuda
Keyword(s):  
Cyclic Amp ◽  
Calcium Channel ◽  
Cell Line ◽  
Calcium Channel Blockers ◽  
Promoter Activity ◽  
Gene Promoter ◽  
Pituitary Cell ◽  
Channel Blockers

Enhancement of Proopiomelanocortin Gene Promoter Activity by Local Anesthetics in a Pituitary Cell Line

2007 ◽  
Vol 32 (1) ◽  
pp. 60-66 ◽  
Author(s):  
Masahiro Ikeda ◽  
Masahiro Kakuyama ◽  
Takehiro Shoda ◽  
Kazuhiko Fukuda
Keyword(s):  
Cell Line ◽  
Local Anesthetics ◽  
Promoter Activity ◽  
Gene Promoter ◽  
Pituitary Cell

Inhibition by calcium channel blockers of the glycogenolytic effect of glucagon in perfused rat liver

1982 ◽  
Vol 99 (4) ◽  
pp. 559-566 ◽  
Author(s):  
Satoshi Kimura ◽  
Toshio Matsumoto ◽  
Ryoko Tada ◽  
Etsuro Ogata ◽  
Kaoru Abe
Keyword(s):  
Cyclic Amp ◽  
Calcium Channel ◽  
Rat Liver ◽  
Calcium Channel Blockers ◽  
Calcium Influx ◽  
Extracellular Calcium ◽  
Channel Blockers ◽  
Perfused Rat Liver ◽  
Glycogenolytic Effect ◽  
Glucose Output

Abstract. Verapamil and diltiazem, calcium channel blockers, inhibited significantly the glucagon-induced glucose output and 45Ca efflux from perfused rat liver at concentrations higher than 50 μm when the perfusate contained calcium. Although the blockers partially interfered with glucagon-induced elevation of cyclic AMP in the tissue, they also inhibited the effects of cyclic AMP. The blockers did not show the inhibitory effects in the absence of perfusate calcium. However, the inhibition of calcium influx into hepatocytes by omission of extracellular calcium or addition of EGTA did not interfere with these effects of glucagon and cyclic AMP. In the presence of extracellular calcium, the blockers did not inhibit cyanide-induced glucose output, indicating that the activity of glycogen phosphorylase and later processes leading to glucose output were not affected by the blockers. These data suggest that, in the presence of calcium, the blockers inhibit the effect of glucagon also at a step (or steps) subsequent to cyclic AMP production and before the activation of phosphorylase b, probably by inhibiting glucagon-induced mobilization of calcium from intracellular calcium pools rather than inhibiting calcium influx into hepatocytes.

Calcium channel blockers Nifedipine and Verapamil protect mouse hepatocytes from both TGF-β and ethanol dependent damage

2008 ◽  
Vol 46 (09) ◽  
Author(s):  
S Ehnert ◽  
A Müller ◽  
A Bachmann ◽  
MV Singer ◽  
S Dooley ◽  
...  
Keyword(s):  
Calcium Channel ◽  
Calcium Channel Blockers ◽  
Channel Blockers ◽  
Mouse Hepatocytes
Sign in / Sign up

Export Citation Format

Share Document