| dc.description.abstract |
The objective of the present study was to assess the effect of lowconcentrations of protein kinase inhibitors on activation. Pig eggs wereelectrostimulated or cultured with the following: 10 µM1-[5-isoquinolinylsulfonyl]-2-methylpiperazine, HCl H7 for 24 h; 100µM H7 for 24 h; 10 nM staurosporine for 24 h; or with 20 µMstaurosporine for 20 min followed by Whitten’s medium for 24 h. Rates ofpronuclear formation in eggs (n = 1240) subjectedto these treatments were: untreated, 6·2%; electrostimulated,77·1%; 10 M H7, 10·0%; 100 µM H7,65%; 10 nM staurosporine, 24·2%; and 20 µMstaurosporine, 67·3% (significance at P£ 0· 05: 10 µM H7 vs untreated, not significant; 20µM staurosporine vs 100 µM H7, notsignificant). Percentages of eggs (n = 125)expressing a 22-kDa band after treatment were: untreated, 37·5%;electrostimulated, 100%; 10 µM H7, 72%; 100 µM H7,66·7%; 10 nM staurosporine, 40 ·0%; and 20µM staurosporine, 77· 3% (significance atP ≤ 0·10: 100 µM H7, 10 nM staurosporineand 20µM staurosporine vs 10 µM H7, not significant; 100 µMH7 and 10 nM staurosporine vs untreated, not significant). Transmissionelectron microscopy of ultrathin sections of treated eggs revealed thatcortical granules were present in over half the untreated eggs, as well asover half of the eggs treated with 100 µM H7 or 10 nM staurosporine; incontrast, all cortical granules were absent from electrically-activated eggs.The results indicate that long-term exposure of eggs to low concentrations ofbroad-spectrum protein kinase inhibitors induces some of the events commonlyassociated with fertilization. |
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