title: Suppression of plasminogen activator production in sheep embryos in vitro after treatment with cycloheximide or ouabain.
abstract: Effects of the metabolic inhibitors cycloheximide and ouabain on development in vitro and plasminogen activator production by sheep embryos were investigated. Embryos (n = 152) from the eight-cell to the morula stage were surgically collected from naturally mated, oestrus-synchronized and superovulated Polypay ewes. In Expt 1, embryos (n = 104) were grouped by cell stage, cultured in Whitten's medium with 1.5% BSA containing 0, 0.1 or 1.0 microgram cycloheximide ml-1 for 24 h, washed and cultured in this medium for 168 h. In Expt 2, morulae (n = 48) were cultured for 48 h in Whitten's medium with 1.5% BSA transferred to the same medium containing 0 or 1.0 mmol ouabain l-1 and cultured for 24 h, and then washed and cultured in this medium for 120 h. At 24 h intervals in both experiments, the medium was recovered and analysed for plasminogen activator. In Expt 1, eight-cell embryos underwent limited development; little difference in the production of plasminogen activator due to cycloheximide treatment was therefore observed. Compared with medium without cycloheximide, treatment with 1.0 microgram cycloheximide ml-1 reduced the number of 16-cell embryos (P < 0.05) and morulae (P < 0.05) (60% versus 10% and 77% versus 8%, respectively) that began to hatch. The mean production of plasminogen activator was greatest in embryos cultured initially as morulae compared with that of 16-cell and eight-cell embryos (P < 0.05). Cycloheximide treatment suppressed the mean production of plasminogen activator in a dose-dependent manner (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Animal Sciences, Oregon State University, Corvallis 97331-6702.
authors.forename: A R
authors.initials: AR
authors.lastname: Menino
authors.forename: J S
authors.initials: JS
authors.lastname: Williams
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D003513:Cycloheximide / Q000494:pharmacology*; D003864:Depression, Chemical; D004305:Dose-Response Relationship, Drug; D004622:Embryo, Mammalian / Q000187:drug effects / Q000378:metabolism*; D005314:Embryonic and Fetal Development / Q000187:drug effects; D010042:Ouabain / Q000494:pharmacology*; D010960:Plasminogen Activators / Q000096:biosynthesis*; D012756:Sheep
chemical_list: D010042:Ouabain; D003513:Cycloheximide; D010960:Plasminogen Activators