Abdelgadir S E, Jaeger J R, Oldfield J E, Appell L H, Stormshak F
Department of Animal Sciences, College of Veterinary Medicine, Oregon State University, Corvallis 97331.
Domest Anim Endocrinol. 1994 Oct;11(4):349-54. doi: 10.1016/0739-7240(94)90006-x.
Two experiments were conducted to study the effects of cycloheximide and colchicine on prostaglandin F2 alpha (PGF2 alpha)-induced secretion and synthesis of oxytocin in bovine luteal tissue in vitro. Corpora lutea were collected from beef heifers on Day 8 of the estrous cycle. In Experiment 1, incorporation of [14C]-leucine into oxytocin synthesized and secreted by luteal slices after exposure to PGF2 alpha, cycloheximide and cycloheximide plus PGF2 alpha was examined. In Experiment 2, synthesis and secretion of oxytocin were evaluated in luteal slices incubated with colchicine and PGF2 alpha alone and in combination. Cycloheximide inhibited incorporation of labeled leucine into luteal proteins by more than 90% and no labeled oxytocin was detected in the media or tissue. Prostaglandin F2 alpha induced significant secretion of oxytocin that was not inhibited by cycloheximide. Tissue levels of oxytocin after incubation with cycloheximide and/or PGF2 alpha did not differ and were similar to those of the incubated control. Colchicine alone did not suppress oxytocin secretion and did not alter the ability of PGF2 alpha to induce significant secretion of this nonapeptide. Tissue concentrations of oxytocin after incubation with colchicine and/or PGF2 alpha did not differ. These studies indicate that secretion and replenishment of luteal oxytocin in vitro is not contingent upon de novo protein synthesis. Inability of colchicine to suppress oxytocin secretion and synthesis may have been due to the short duration of exposure of luteal tissue to the drug.
进行了两项实验，以研究放线菌酮和秋水仙碱对体外培养的牛黄体组织中前列腺素F2α（PGF2α）诱导的催产素分泌和合成的影响。在发情周期的第8天从肉用小母牛收集黄体。在实验1中，检测了在暴露于PGF2α、放线菌酮以及放线菌酮加PGF2α后，[14C]-亮氨酸掺入黄体切片合成和分泌的催产素中的情况。在实验2中，评估了单独以及联合用秋水仙碱和PGF2α孵育的黄体切片中催产素的合成和分泌。放线菌酮抑制标记的亮氨酸掺入黄体蛋白超过90%，并且在培养基或组织中未检测到标记的催产素。前列腺素F2α诱导催产素显著分泌，而这并未被放线菌酮抑制。用放线菌酮和/或PGF2α孵育后，组织中的催产素水平没有差异，并且与孵育对照的水平相似。单独使用秋水仙碱不抑制催产素分泌，也不改变PGF2α诱导这种九肽显著分泌的能力。用秋水仙碱和/或PGF2α孵育后，组织中催产素的浓度没有差异。这些研究表明，体外黄体催产素的分泌和补充并不取决于从头合成蛋白质。秋水仙碱不能抑制催产素分泌和合成可能是由于黄体组织与该药物接触的时间较短。
