TY - JOUR
T1 - Function of Ca2+ influx in phospholipase D activation induced by prostaglandin F2α in osteoblast-like cells
T2 - Involvement of tyrosine kinase
AU - Kozawa, O.
AU - Suzuki, A.
AU - Watanabe, Y.
AU - Shinoda, J.
AU - Oiso, Y.
PY - 1995/5
Y1 - 1995/5
N2 - We previously reported that prostaglandin F2α (PGF2α) induces Ca2+ influx from the extracellular space via protein tyrosine kinase in osteoblast-like MC3T3-E1 cells and that PGF2α stimulates phosphatidylcholine-hydrolyzing phospholipase D in these cells (6, 12). In this study, we examined the relationship between the tyrosine kinase-regulated Ca2+ influx by PGF2α and the activation of phospholipase D in MC3T3-E1 cells. The depletion of extracellular Ca2+ by [ethylenebis(oxyethylenenitrilo)]tetraacetic acid (EGTA) markedly reduced the PGF2α-induced formation of choline. Genistein, an inhibitor of protein tyrosine kinases, which by itself had little effect on choline formation, significantly suppressed the formation of choline induced by PGF2α in a dose-dependent manner. Tyrphostin, an inhibitor of protein tyrosine kinases chemically distinct from genistein, also suppressed the PGF2α-induced formation of choline. Sodium orthovanadate, an inhibitor of protein tyrosine phosphatases, significantly enhanced the PGF2α-induced formation of choline. These results strongly suggest that the phospholipase D activation by PGF2α is dependent on extracellular Ca2+ in osteoblast-like cells and that protein tyrosine kinase is involved in the activation of phospholipase D.
AB - We previously reported that prostaglandin F2α (PGF2α) induces Ca2+ influx from the extracellular space via protein tyrosine kinase in osteoblast-like MC3T3-E1 cells and that PGF2α stimulates phosphatidylcholine-hydrolyzing phospholipase D in these cells (6, 12). In this study, we examined the relationship between the tyrosine kinase-regulated Ca2+ influx by PGF2α and the activation of phospholipase D in MC3T3-E1 cells. The depletion of extracellular Ca2+ by [ethylenebis(oxyethylenenitrilo)]tetraacetic acid (EGTA) markedly reduced the PGF2α-induced formation of choline. Genistein, an inhibitor of protein tyrosine kinases, which by itself had little effect on choline formation, significantly suppressed the formation of choline induced by PGF2α in a dose-dependent manner. Tyrphostin, an inhibitor of protein tyrosine kinases chemically distinct from genistein, also suppressed the PGF2α-induced formation of choline. Sodium orthovanadate, an inhibitor of protein tyrosine phosphatases, significantly enhanced the PGF2α-induced formation of choline. These results strongly suggest that the phospholipase D activation by PGF2α is dependent on extracellular Ca2+ in osteoblast-like cells and that protein tyrosine kinase is involved in the activation of phospholipase D.
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U2 - 10.1016/0952-3278(95)90033-0
DO - 10.1016/0952-3278(95)90033-0
M3 - Article
C2 - 7630920
AN - SCOPUS:0028989142
SN - 0952-3278
VL - 52
SP - 319
EP - 323
JO - Prostaglandins, Leukotrienes and Essential Fatty Acids
JF - Prostaglandins, Leukotrienes and Essential Fatty Acids
IS - 5
ER -