title: Effect of cytochalasins B and D on the developmental competence of somatic cell nuclear transfer embryos in miniature pigs.
abstract: In many animals, cytochalasins have generally been used as cytoskeletal inhibitors for the diploid complement retention of somatic cell nuclear transfer (SCNT) embryos. However, limited information is available on the effects of cytochalasins on the in vitro development of SCNT embryos. Hence, we compared the effects of cytochalasin B (CB) and cytochalasin D (CD) on pseudo-polar body (pPB) extrusion, cortical actin filament (F-actin) distribution in porcine parthenogenetic oocytes and in vitro development of SCNT embryos that were reconstructed using foetal fibroblasts in the G0/G1 phase derived from miniature pigs. CB (7.5 microg/ml) and CD (2.5 microg/ml) treatments effectively inhibited pPB extrusion in SCNT embryos. CB (2.5 microg/ml) treatment could not inhibit pPB extrusion and insufficiently destabilized F-actin immediately following artificial activation. In parthenogenetic oocytes treated with 2.5 microg/ml CD, normal reorganization and uniform distribution of cortical F-actin at the cytoplasmic membrane were observed at 8 h after artificial activation; this finding was similar to that of control oocytes. In contrast, parthenogenetic oocytes treated with 7.5 microg/ml CB showed non-uniform distribution of F-actin at 8 h after artificial activation. On day 5 after in vitro cultivation, the blastocyst formation rate of SCNT embryos treated with 2.5 microg/ml CD was significantly higher than that of SCNT embryos treated with 2.5 and 7.5 microg/ml CB (p < 0.05). Hence, the present findings suggest that CD is more effective than CB as the cytoskeletal inhibitor for the production of SCNT embryos in miniature pigs.
authors.affiliation: Laboratory of Animal Reproduction, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-amamiyamachi, Aoba-ku, Sendai 981-8555, Japan. s-sugimura@bios.tohoku.ac.jp
authors.forename: Satoshi
authors.initials: S
authors.lastname: Sugimura
authors.forename: Manabu
authors.initials: M
authors.lastname: Kawahara
authors.forename: Takuya
authors.initials: T
authors.lastname: Wakai
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Yamanaka
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sasada
authors.forename: Eimei
authors.initials: E
authors.lastname: Sato
mesh_terms: D008841:Actin Cytoskeleton / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D002453:Cell Cycle; D003571:Cytochalasin B / Q000494:pharmacology*; D015638:Cytochalasin D / Q000494:pharmacology*; D047108:Embryonic Development / Q000187:drug effects*; D053652:Nuclear Transfer Techniques; D009865:Oocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D010312:Parthenogenesis; D013552:Swine; D013556:Swine, Miniature / Q000196:embryology*
chemical_list: D015638:Cytochalasin D; D003571:Cytochalasin B