Inagaki N, Suzuki S, Kitai H, Nakatogawa N, Kuji N, Iwahashi K, Yoshimura Y
Department of Obstetrics and Gynecology, Saitama Chuo Hospital, Japan.
J Assist Reprod Genet. 1997 Nov;14(10):609-16. doi: 10.1023/a:1022541020458.
Our purpose was to determine the association of calmodulin-dependent protein kinase II (CaMKII) with oocyte activation and to explore the network of protein kinases during mammalian fertilization.
Mouse M-II oocytes were collected after superovulation induced by PMSG-hCG injection. The oocytes were inseminated or artificially activated by Ca ionophore (A23187) or 12-O-tetradecanoyl phorbol 13-acetate (TPA). The effects of KN-62, a specific and selective inhibitor of calmodulin-dependent protein kinase II, on second polar body emission (2PBE), pronuclear formation (PF), and cortical granule exocytosis (CGE) during fertilization or after artificial oocyte activation were investigated.
KN-62 inhibited 2PBE and PF after sperm or Ca ionophore inducing activation. Additionally, PF was inhibited by KN-62 after TPA activation, whereas KN-62 did not inhibit CGE in any case. KN-04, an inactive form of KN-62, did not inhibit significantly 2PBE, CGE, or PF. When oocytes were exposed to KN-62 after Ca ionophore or TPA activation, no inhibitory effects on 2PBE or PF were observed.
The CaMKII activation that occurs after fertilization or artificial activation of mouse oocytes is presumably secondary to increases in the intracellular free calcium concentration. As determined by the use of inhibitor, CaMKII activity is associated with 2PBE and PF but not with CGE.
我们的目的是确定钙调蛋白依赖性蛋白激酶II（CaMKII）与卵母细胞激活之间的关联，并探索哺乳动物受精过程中的蛋白激酶网络。
通过注射孕马血清促性腺激素（PMSG）-人绒毛膜促性腺激素（hCG）诱导超排卵后收集小鼠M-II期卵母细胞。卵母细胞经精子受精，或用钙离子载体（A23187）或十四酰佛波醇乙酯（TPA）进行人工激活。研究了钙调蛋白依赖性蛋白激酶II的特异性选择性抑制剂KN-62对受精过程中或人工卵母细胞激活后第二极体排放（2PBE）、原核形成（PF）和皮质颗粒胞吐作用（CGE）的影响。
KN-62在精子或钙离子载体诱导激活后抑制2PBE和PF。此外，TPA激活后KN-62抑制PF，而KN-62在任何情况下均不抑制CGE。KN-04是KN-62的无活性形式，对2PBE、CGE或PF无明显抑制作用。当卵母细胞在钙离子载体或TPA激活后暴露于KN-62时，未观察到对2PBE或PF的抑制作用。
小鼠卵母细胞受精或人工激活后发生的CaMKII激活可能继发于细胞内游离钙浓度的升高。通过使用抑制剂确定，CaMKII活性与2PBE和PF相关，但与CGE无关。
