Meier S, Lau T M, Jenkin G, Fairclough R J
Department of Physiology, Monash University, Clayton, Victoria, Australia.
J Reprod Fertil. 1995 Mar;103(2):233-8. doi: 10.1530/jrf.0.1030233.
Endometrial oxytocin receptor concentrations and oxytocin-induced plasma concentrations of 13,14,dihydro-15-keto prostaglandin F2 alpha were investigated on days 14 and 17 of the oestrous cycle and on days 14, 17, 25, 65, 85 and 145 of gestation in ewes. Total 13,14,dihydro-15-keto prostaglandin F2 alpha release in response to a bolus injection of oxytocin was significantly (P < 0.05) higher at luteolysis (day 17 of the oestrous cycle) than at any other stage of the oestrous cycle or in early gestation. On days 65, 85 and 145 of gestation, total prostaglandin release was significantly (P < 0.05) increased compared with earlier in gestation. Maximum concentrations of 13,14,dihydro-15-keto prostaglandin F2 alpha in response to oxytocin followed a similar pattern. Oxytocin receptor concentrations reflected total oxytocin-induced 13,14,dihydro-15-keto prostaglandin F2 alpha release, with increased oxytocin receptor concentrations occurring on day 17 of the oestrous cycle, compared with those observed on day 14 of the oestrous cycle and on days 14, 17 and 25 of gestation. By day 65 of gestation, oxytocin receptor concentrations were again increased. However, on days 85 and 145 of gestation, oxytocin receptor concentrations had decreased to concentrations similar to those observed in early gestation. These results indicate that oxytocin-induced 13,14,dihydro-15-keto prostaglandin F2 alpha release during early gestation is minimal despite the presence of endometrial oxytocin receptors. In mid-gestation, oxytocin-stimulated 13,14,dihydro-15-keto prostaglandin F2 alpha release is increased with a concomitant increase in uterine oxytocin receptor concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)
在母羊发情周期的第14天和第17天以及妊娠的第14、17、25、65、85和145天，研究了子宫内膜催产素受体浓度以及催产素诱导的血浆13,14-二氢-15-酮前列腺素F2α浓度。在黄体溶解期（发情周期第17天），静脉注射催产素后，13,14-二氢-15-酮前列腺素F2α的总释放量显著高于发情周期的任何其他阶段或妊娠早期（P<0.05）。在妊娠第65、85和145天，与妊娠早期相比，前列腺素总释放量显著增加（P<0.05）。对催产素反应的13,14-二氢-15-酮前列腺素F2α的最大浓度呈现类似模式。催产素受体浓度反映了催产素诱导的13,14-二氢-15-酮前列腺素F2α的总释放量，与发情周期第14天以及妊娠第14、17和25天相比，发情周期第17天催产素受体浓度增加。到妊娠第65天时，催产素受体浓度再次升高。然而，在妊娠第85和145天，催产素受体浓度已降至与妊娠早期观察到的浓度相似。这些结果表明，尽管存在子宫内膜催产素受体，但妊娠早期催产素诱导的13,14-二氢-15-酮前列腺素F2α释放量极少。在妊娠中期，催产素刺激的13,14-二氢-15-酮前列腺素F2α释放量增加，同时子宫催产素受体浓度也随之增加。（摘要截断于250字）
