Butyrolactone I reversibly alters nuclear configuration, periooplasmic microtubules and development of porcine oocytes.
In the present study, we investigated the effects of specific cdc2 kinase inhibitor, butyrolactone I (BL I) on the prevention of germinal vesicle breakdown, changes of microtubular structures, and development of porcine oocytes after removal of the drug. In Experiment 1, cumulus-oocyte complexes (COCs) were cultured (44 h) in NCSU-23 medium containing different concentrations of BL I. The percentages of oocytes remaining at GV stage were 0, 0, 32, 80, and 84% (P<0.05), and the maturation rates were 86, 63, 30, 0, and 0% (P<0.05) for oocytes treated with 0, 10, 20, 40, and 80 microM of BL I, respectively. When oocytes were released from BL I incubation (Experiment 2) and cultured for an additional 44 h, 79, 84, and 83% of oocytes resumed meiosis, but only 52, 38 and 17% of oocytes reached normal metaphase II (MII) stage in the groups treated with 20, 40 and 80 microM BL I, respectively. In Experiments 3-5, reversibility and development of oocytes and embryos were evaluated after removal of the inhibitor. A reduced duration of BL I incubation (22 h) at 20 microM increased the percentage of oocytes remaining at the GV stage compared to the control group (85% versus 9%, P<0.05). Blastocyst rates were lower in treatment groups than in the control (44 h) group (0-14% versus 24%; P<0.05). However, all developing blastocysts possessed similar cell numbers, regardless of the drug-treated or non-treated controls. Taken together, treatment with 20-80 microM of BL I effectively prevented the resumption of meiosis and polymerization of periooplasmic microtubules. Furthermore, reversibility of the oocytes after reduced duration of BL I treatment was satisfactory.
Weng
Ya-Chi
YC
Department of Animal Science, National Chia-Yi University, Chia-Yi 600, Taiwan, ROC.
Sha
Shi-Wen
SW
Chiou
Chii-Ming
CM
Tang
Pin-Chi
PC
Yang
Jeng-Huh
JH
Ju
Jyh-Cherng
JC
D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000494:pharmacology; D000818:Animals; D002467:Cell Nucleus / Q000187:drug effects*; D002478:Cells, Cultured; D002843:Chromatin / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D008540:Meiosis / Q000187:drug effects; D008870:Microtubules / Q000187:drug effects*; D009865:Oocytes / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development; D010312:Parthenogenesis / Q000187:drug effects; D047428:Protein Kinase Inhibitors / Q000494:pharmacology*; D013552:Swine / Q000502:physiology*; D013997:Time Factors
D002843:Chromatin; D047428:Protein Kinase Inhibitors; C082868:butyrolactone I; D015107:4-Butyrolactone