[Inhibition of the reinitiation of meiosis in Xenopus laevis oocytes by three natural antiproteases: antipain, chymostatin, and leupeptin].
Oocytes incubated for 1 hr. in saline containing 1 mg/ml of antipain, leupeptin or chymostatin do not reinstate meiosis when progesterone or ionophore A 23187 are added. On the contrary such oocytes remain able to undergo meiosis when injected with cytoplasm of maturing oocytes (MPF), with Rabbit phosphorylase kinase or with Beef protein kinase. These results demonstrate that the loss of responsiveness to progesterone or ionophore is not due to toxic effects but rather to some interference with a key event which occurs prior to MPF action.
D000818:Animals; D000001:Calcimycin / Q000494:pharmacology; D002403:Cathepsins / Q000037:antagonists & inhibitors; D002918:Chymotrypsin / Q000037:antagonists & inhibitors*; D005260:Female; D008540:Meiosis / Q000187:drug effects*; D009865:Oocytes / Q000187:drug effects*; D010063:Ovum / Q000187:drug effects*; D010206:Papain / Q000037:antagonists & inhibitors; D010764:Phosphorylase Kinase / Q000378:metabolism; D011374:Progesterone / Q000494:pharmacology; D011494:Protein Kinases / Q000378:metabolism; D014361:Trypsin Inhibitors / Q000494:pharmacology*; D014981:Xenopus
D014361:Trypsin Inhibitors; D000001:Calcimycin; D011374:Progesterone; D011494:Protein Kinases; D010764:Phosphorylase Kinase; D002403:Cathepsins; D002918:Chymotrypsin; D010206:Papain
Inhibition de la réinitiation de la méiose des ovocytes de Xenopus laevis par trois antiprotéases naturelles, l'antipïne, la chymostatine et la leupeptine