Induction of prostaglandin I(2) receptor by tumor necrosis factor alpha in osteoblastic MC3T3-E1 cells.
Mouse osteoblastic cells MC3T3-E1 produced prostaglandin E(2) via the reaction of cyclooxygenase-2 enzyme induced by tumor necrosis factor alpha (TNFalpha). Originally, the mRNA level for prostaglandin I(2) receptor (IP) was low in the cells. However, the addition of TNFalpha brought about a marked increase in the IP mRNA with a lag of about 3 h up to an about 8-fold higher level for 24 h. In addition, the induction of IP was supported by a binding experiment of [(3)H]iloprost (a stable analogue of prostaglandin I(2)). The amount of iloprost bound to the TNFalpha-stimulated cell membranes increased to a saturation level around 30 nM. Dexamethasone, cycloheximide and cyclooxygenase inhibitor suppressed the IP mRNA induction. The finding with the latter two compounds suggested a TNFalpha-dependent de novo synthesis of a protein, which is involved in the IP mRNA induction and may be attributed partially to the induced cyclooxygenase-2.
Wang
J
J
Department of Biochemistry, University of Tokushima, School of Medicine, 3-18-15 Kuramoto-cho, Tokushima, Japan.
Yamamoto
K
K
Sugimoto
Y
Y
Ichikawa
A
A
Yamamoto
S
S
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D001241:Aspirin / Q000494:pharmacology; D015152:Blotting, Northern; D002460:Cell Line; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D003907:Dexamethasone / Q000494:pharmacology; D016285:Iloprost / Q000378:metabolism; D051379:Mice; D009578:Nitrobenzenes / Q000494:pharmacology; D010006:Osteoblasts / Q000187:drug effects* / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis; D044006:Receptors, Epoprostenol; D011982:Receptors, Prostaglandin / Q000096:biosynthesis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012886:Skull; D013449:Sulfonamides / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors / Q000494:pharmacology*
D000893:Anti-Inflammatory Agents; D000894:Anti-Inflammatory Agents, Non-Steroidal; D009578:Nitrobenzenes; D012333:RNA, Messenger; D044006:Receptors, Epoprostenol; D011982:Receptors, Prostaglandin; D013449:Sulfonamides; D014409:Tumor Necrosis Factor-alpha; C080955:N-(2-cyclohexyloxy-4-nitrophenyl)methanesulfonamide; D003907:Dexamethasone; D016285:Iloprost; D001241:Aspirin