Shamay A, Cohen N, Madar Z, Levin I, Gertler A
Department of Biochemistry and Human Nutrition, Hebrew University of Jerusalem, Rehovot, Israel.
J Dairy Sci. 1989 May;72(5):1169-74. doi: 10.3168/jds.S0022-0302(89)79220-1.
Bovine mammary gland tissue from 4- to 6-mo-old calves was grafted s.c. (dorsum) to 7- to 9-wk-old female athymic "nude" mice. The graft-bearing mice were divided into three groups and were treated with the following hormonal combinations: 1) implantation of a pellet containing estrogen and progesterone followed by injection of estrogen and progesterone, 2) injections of estrogen and progesterone, and 3) injections of estrogen, progesterone, and prolactin. Following in vivo treatment, the grafts were removed and prepared for organ culture. Explants from each treatment were subdivided into two hormonal regimens: 1) insulin and cortisol; 2) insulin, cortisol, and prolactin. An increase in in vitro fat synthesis was observed in explants cultured in the presence of prolactin. This increase was not affected by previous in vivo hormonal treatment. In vitro casein synthesis was not stimulated by the presence of prolactin in the culture medium; however, casein secretion was elevated in explants from grafts from animals that were treated in vivo with estrogen, progesterone, and prolactin. Casein secretion was further increased in explants cultured in the presence of prolactin but rapidly dropped in its absence. Explants that were not implanted in mice responded in long-term organ culture similarly to explants pretreated in vivo.
将4至6月龄犊牛的乳腺组织皮下移植（背部）到7至9周龄的雌性无胸腺“裸”鼠体内。将移植有组织的小鼠分为三组，并用以下激素组合进行处理：1）植入含雌激素和孕酮的药丸，随后注射雌激素和孕酮；2）注射雌激素和孕酮；3）注射雌激素、孕酮和催乳素。体内处理后，取出移植物并准备进行器官培养。每种处理的外植体再分为两种激素处理方案：1）胰岛素和皮质醇；2）胰岛素、皮质醇和催乳素。在含有催乳素的培养基中培养的外植体中观察到体外脂肪合成增加。这种增加不受先前体内激素处理的影响。培养基中催乳素的存在并未刺激体外酪蛋白合成；然而，在用雌激素、孕酮和催乳素进行体内处理的动物的移植物外植体中，酪蛋白分泌升高。在含有催乳素的培养基中培养的外植体中，酪蛋白分泌进一步增加，但在无催乳素的情况下迅速下降。未植入小鼠体内的外植体在长期器官培养中的反应与体内预处理的外植体相似。
