Williams J
I.N.R.A., Monnaie, France.
Reprod Nutr Dev (1980). 1988;28(4B):1081-91. doi: 10.1051/rnd:19880706.
Hens in their sixth month of lay were injected with a series of doses of ovine LH, either following the oviposition of a mid-sequence egg (which is closely associated with an ovulation), or following the oviposition of the last egg of a sequence. The concentrations of steroid hormones were subsequently measured by radioimmunoassay in blood withdrawn at intervals after injection. No changes were observed in the concentrations of either testosterone or 17 beta-oestradiol, irrespective of the dose of LH or the stage of the ovulatory cycle. An increase in delta-4-androstenedione was observed in all cases. This increase was minimal and unrelated to the dose of LH at the mid-sequence stage, but a dose-response relationship was observed in hens injected following the terminal oviposition of a series. Consistent, dose-related changes in the concentrations of progesterone in plasma were found at both stages of the ovulatory cycle, and the magnitude of these changes was 3.5-5 times greater than those observed for androstenedione. Granulosa cells from the first, second and third ovarian follicles were dispersed by collagenase and stimulated with ovine LH either immediately or following a 24 h pre-incubation in medium 199. The amount of progesterone released into the medium after 3 h was assessed by radioimmunoassay. A progressive decrease in this response was observed in cells derived from the first to the third follicles in all cases. Cells challenged after 24 h always showed increased responses, cells from the second follicle secreted similar amounts of progesterone as cells from the first follicle that were challenged immediately, without pre-incubation. The responses obtained after 24 h were attenuated if no bovine serum albumin was present in the medium, or if ovine LH had been present in the medium continuously. These results are interpreted as evidence for an increase in the secretion of progesterone by the granulosa cells of the hen which is linked to the maturation of the follicle. The final stages of this maturation may proceed in the absence of LH.
处于产蛋第六个月的母鸡，在序列中期的一枚蛋（与一次排卵密切相关）产出后，或者在序列中最后一枚蛋产出后，注射一系列剂量的羊促黄体素（oLH）。随后，通过放射免疫分析法测定注射后每隔一段时间抽取的血液中类固醇激素的浓度。无论促黄体素的剂量或排卵周期的阶段如何，睾酮或17β-雌二醇的浓度均未观察到变化。在所有情况下，均观察到Δ4-雄烯二酮增加。这种增加在序列中期阶段最小，且与促黄体素的剂量无关，但在一系列蛋的最终排卵后注射促黄体素的母鸡中观察到剂量反应关系。在排卵周期的两个阶段，血浆中孕酮浓度均出现与剂量相关的一致变化，且这些变化的幅度比观察到的雄烯二酮变化大3.5至5倍。用胶原酶分散来自第一、第二和第三卵巢卵泡的颗粒细胞，并立即或在199培养基中预孵育24小时后用羊促黄体素刺激。通过放射免疫分析法评估3小时后释放到培养基中的孕酮量。在所有情况下，从第一个卵泡到第三个卵泡来源的细胞中均观察到这种反应逐渐降低。24小时后受到刺激的细胞总是表现出反应增加，来自第二个卵泡的细胞分泌的孕酮量与立即受到刺激、未预孵育的来自第一个卵泡的细胞相似。如果培养基中不存在牛血清白蛋白，或者培养基中一直存在羊促黄体素，则24小时后获得的反应会减弱。这些结果被解释为母鸡颗粒细胞孕酮分泌增加的证据，这与卵泡成熟有关。这种成熟的最后阶段可能在没有促黄体素的情况下进行。
