Ljunggren O, Fredholm B B, Nordstedt C, Ljunghall S, Lerner U H
Department of Internal Medicine, University Hospital, Uppsala, Sweden.
Eur J Pharmacol. 1993 Jan 15;244(2):111-7. doi: 10.1016/0922-4106(93)90015-2.
Bradykinin (1 microM, 5 min) induced translocation of protein kinase C (PKC) to the plasma membrane fraction in osteoblastic MC3T3-E1 cells. Bradykinin also enhanced the binding of phorbol 12,13-dibutyrate (PDBu) to intact cells, a measure of PKC activation. Addition of bradykinin (1 microM) to cells preincubated with [3H]PDBu (10 nM, 20 min) caused an increase in specific PDBu binding that was maximal after 5-10 min. The bradykinin-induced enhancement of PDBu binding was seen at 1 nM and was maximal at 10 nM. The bradykinin B1 receptor agonist des-Arg9-bradykinin (1 microM) did not enhance specific PDBu binding to intact MC3T3-E1 cells. PDBu at and above 3 nM stimulated the formation of prostaglandin E2 (PGE2) in MC3T3-EI cells. This stimulatory effect was seen after 15-20 min incubation. The Ca2+ ionophore A23187 at and above 1 microM induced a rapid (within seconds) burst of PGE2 formation in MC3T3-E1 cells. The effect of PDBu and A23187 on PGE2 formation was synergistic. The PKC inhibitor staurosporine (200 nM) inhibited basal as well as bradykinin-induced prostaglandin-formation in MC3T3-E1 cells.
bradykinin enhances PKC activation in osteoblastic MC3T3-E1 cells. This kinase activation may be involved in bradykinin-induced prostaglandin formation.
缓激肽（1微摩尔，5分钟）可诱导成骨细胞MC3T3-E1细胞中的蛋白激酶C（PKC）转位至质膜部分。缓激肽还增强了佛波醇12,13-二丁酸酯（PDBu）与完整细胞的结合，这是PKC活化的一种指标。向预先用[3H]PDBu（10纳摩尔，20分钟）孵育的细胞中添加缓激肽（1微摩尔）会导致特异性PDBu结合增加，在5-10分钟后达到最大值。缓激肽诱导的PDBu结合增强在1纳摩尔时即可观察到，在10纳摩尔时达到最大值。缓激肽B1受体激动剂去-精氨酸9-缓激肽（1微摩尔）不会增强特异性PDBu与完整MC3T3-E1细胞的结合。3纳摩尔及以上浓度的PDBu刺激MC3T3-EI细胞中前列腺素E2（PGE2）的形成。这种刺激作用在孵育15-20分钟后可见。1微摩尔及以上浓度的钙离子载体A23187在MC3T3-E1细胞中诱导PGE2形成的快速（数秒内）爆发。PDBu和A23187对PGE2形成的作用是协同的。PKC抑制剂星形孢菌素（200纳摩尔）抑制MC3T3-E1细胞中的基础以及缓激肽诱导的前列腺素形成。
缓激肽增强成骨细胞MC3T3-E1细胞中的PKC活化。这种激酶活化可能参与缓激肽诱导的前列腺素形成。
