ミニチュア ブタ ノ オウタイ カイカ キ ニ オケル プロスタグランジF_2α レンゾク トウヨ ガ ケッチュウ セイ ステロイドホルモン ノウド オヨビ チツナイ セイリ ショ セイジョウ ニ オヨボス エイキョウ

PGF_2αの単独投与が血中性ステロイドホルモン濃度の動態および腟内生理諸性状に及ぼす影響について検討した。供試動物は,本学家畜繁殖学研究室にて飼育管理されている正常な発情周期を示すミニチュアブタ10頭を用いた。PGF_2αは,クロプロステノール0.25mg/ml含有しているものを用いた。PGF_2α投与は,試験区として,(1)1.0mgの単回投与,(2)0.5mgの2回投与,(3)1.5mgの2回投与,(4)1.0mgの3回投与に区分し,対照区として生理食塩水投与区とした。いずれの投与区においても黄体開花期(Day7 ; 排卵日=Day0)より,腟前庭粘膜下へ投与した。その結果,PGF_2α投与区(1),(2)においては1頭を除いた他の個体は19.7±0.7日(Mean±SE)であった。しかし,PGF_2α投与区(3)および(4)において,発情周期は排卵日より12.3±0.3日であり,対照区(18.7±0.9日)と比較して有意(P<0.05)に短縮を示した。また,これらの投与区においての腟垢内剥離上皮細胞の出現率および腟内電気抵抗値も正常な個体の発情期と同様の結果を示した。以上のことより,ミニチュアブタにおいてPGF_2α投与により発情周期を短縮させることは可能であり,本法を用いての発情および排卵の同期化へ応用が示唆された。In this study we investigated the effect of PGF_2α administration on the kinetics of sex steroid hormone and physiological properties of vagina. PGF_2α administrations divided into 5 groups, (1) 1.0mg PGF_2α, (2) 0.5mg×2 times given of 12hs. interval, (3) 1.5×2, (4) 1.0mg×3, (5) no treatment (physiological salt solution=Control) were examined in a total of 10 pigs. In all experimental groups, the concentration of Progesterone (P_4) tended to decrease just after PGF_2α treatment. But more than 3.0mg PGF_2α decreased and kept the concentration of progesterone at less than 1.0ng/ml. Estrous cycle of groups (3, 4) were significantly shorter than that of group (1), (12.3±0.3 days vs. 18.7±0.9days, P<0.05). In addition, vagina physiological properties of group (3, 4) were normal. In conclusion, multiple administration of PGF_2α is useful for the synchronization of pig estrous cycle

Addition of granulosa cells collected from differential follicle stages supports development of oocytes derived from porcine early antral follicles

Abstract Purpose Improvement of in vitro oocyte growth by addition of granulosa cells derived from differential developmental stages of follicles. Methods Granulosa cells (GCs) collected from either early antral follicles (EAFs) or antral follicles (AFs) were added to oocyte‐granulosa cell complexes (OGCs) derived from EAFs, and the in vitro growth of the oocytes was evaluated. Results Granulosa cells were incorporated into OGCs to form new OGCs within 2 days of culture. After 14 days of culture, the number of GCs surrounding oocytes was similar among the three OGCs conditions (unmanipulated “natural OGCs,” “EAF‐GCs add OGCs,” and “AF‐GCs add OGCs”), whereas the survival rate of the GCs and diameter of oocytes grown in vitro were the greatest for “AF‐GCs added OGCs.” After parthenogenetic activation, developmental rate till the blastocyst stage tended to be higher for “AF‐GCs add OGCs” compared with other groups. Addition of AF‐GCs significantly increased a hypoxic marker (pimonidazole staining) and increased the lipid content in oocytes grown in vitro compared with unmanipulated OGCs. Conclusion Addition of GCs derived from more advanced stages of follicles to the OGCs changes the metabolism of oocytes and is beneficial for in vitro growth of oocytes derived from EAFs