Ford M M, Thorburn G D, Caddy D J, Young I R
Department of Physiology, Monash University, Clayton, Victoria 3168, Australia.
Biol Reprod. 1999 Aug;61(2):411-5. doi: 10.1095/biolreprod61.2.411.
Prostaglandin (PG) F(2alpha) secreted from the uterus is the luteolysin of the estrous cycle and is also believed to be responsible for luteolysis in the pregnant doe at term. We have reported that basal progesterone concentrations decrease before basal PGF(2alpha) concentrations increase, which is inconsistent with this view. In this study we investigated whether luteolysis is associated with increased frequency or amplitude of pulsatile PGF(2alpha) secretion in does over the last 2 wk of gestation. Progesterone concentrations decreased approximately 1 wk before parturition. There was no accompanying increase in PGF(2alpha) concentrations or pulse frequency, and those pulses that were observed were of lesser amplitude and duration than those that have been associated with luteolysis in cycling ewes. A small increase in PGF(2alpha) pulse frequency was identified during the 3 days before parturition, but this was not associated with any change in progesterone concentrations. The biological significance of these small changes in PGF(2alpha) pulse frequency is obscure, although the high concentration of this eicosanoid at labor may have been related to the final, precipitous decline in plasma progesterone concentrations. These findings do not support the notion that PGF(2alpha) is the principal luteolysin in the pregnant doe at term.
子宫分泌的前列腺素（PG）F(2α)是发情周期中的溶黄体素，也被认为是足月妊娠母鹿黄体溶解的原因。我们曾报道基础孕酮浓度在基础PGF(2α)浓度升高之前就已下降，这与该观点不一致。在本研究中，我们调查了妊娠最后2周母鹿的黄体溶解是否与脉冲式PGF(2α)分泌频率或幅度增加有关。孕酮浓度在分娩前约1周下降。PGF(2α)浓度或脉冲频率没有随之增加，且观察到的那些脉冲的幅度和持续时间比与发情期母羊黄体溶解相关的脉冲要小。在分娩前3天，PGF(2α)脉冲频率有小幅增加，但这与孕酮浓度的任何变化均无关。尽管分娩时这种类花生酸的高浓度可能与血浆孕酮浓度的最终急剧下降有关，但PGF(2α)脉冲频率这些微小变化的生物学意义尚不清楚。这些发现不支持PGF(2α)是足月妊娠母鹿主要溶黄体素的观点。
