Stimulation of glycogen degradation by prostaglandin E2 in primary cultured rat hepatocytes.
Hepatocytes isolated from rats by the collagenase perfusion method were cultured as monolayers at concentrations of 0.4-1.1 x 10(6) attached cells/dish (9 cm2) for 1-3 days and the effect of prostaglandins on their glycogenolysis was studied. By use of [14C]glycogen-labeled cells, prostaglandin E2 (PGE2) was found to have a stimulatory effect on glycogen degradation at high cell density (more than 0.8 x 10(6) cells/dish) in 1-day cultures. PGE2 was maximally effective at 10(-7) M, increasing [14C]release from cellular [14C]glycogen to 2-3 times the basal level after 1 h incubation, and to plateau level within 2 h. PGE1, 16,16-dimethyl PGE2 and PGF2 alpha had similar effects, but PGD2 and dinor-PGE1 (a metabolite of PGE1 and PGE2 in hepatocytes) had no effect. This prostaglandin-induced glycogen degradation was observed in 1-day cultures, with a maximum between 20-30 h, but not in 2-day and later cultures. Treatment of hepatocytes with pertussis toxin potentiated PGE2-stimulated glycogen degradation, indicating that the effect involves a different pathway from that for inhibition of glucagon- and epinephrine-stimulated glycogenolysis by E series prostaglandins reported previously.
Kanemaki
T
T
First Department of Surgery, Kansai Medical University, Osaka, Japan.
Kitade
H
H
Hiramatsu
Y
Y
Kamiyama
Y
Y
Okumura
T
T
D000818:Animals; D002452:Cell Count; D002478:Cells, Cultured; D015232:Dinoprostone / Q000494:pharmacology; D008099:Liver / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D008112:Liver Glycogen / Q000378:metabolism*; D008297:Male; D011453:Prostaglandins / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
D008112:Liver Glycogen; D011453:Prostaglandins; D015232:Dinoprostone