Steroid metabolism by the bovine uterine endometrium and conceptus.
Steroid metabolism by the bovine uterine endometrium and conceptus.
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类固醇通过牛子宫内膜和孕体代谢。
DOI：
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发表时间：
1983
影响因子：
3.6
通讯作者：
Michael J. Fields
中科院分区：
文献类型：
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作者：
Robert Eley;W. Thatcher;F. Bazer;Michael J. Fields
对两种子宫特异性组织（即子宫内膜和孕体）代谢中性类固醇的体外能力进行了比较。在配种后第16、19、23和27天（D）屠宰时从55头奶牛中获得组织。D16和D19子宫中不含任何受孕产物的被指定为非妊娠（NP）;那些带膜的被指定为妊娠（P）。将子宫内膜（500 mg）和子宫内膜（完整或减半）组织（n-227）在含有10 ng同位素标记的孕酮（P4）或雄烯二酮（A）的最小必需培养基（MEM）中孵育。通过化学转化前后的提取和色谱柱分离，测定甾体代谢产物的代谢程度和定性评价。通过重结晶至与真实放射性惰性母体化合物的恒定比活度，验证代谢物的鉴别和定量。两种底物均被组织广泛代谢，3 h内的代谢量大于1 h（P<0.001）。在D16和D19，子宫内膜组织代谢相似量的P4/mg组织，与生殖状态（P vs. NP）或子宫内组织的位置无关。D27子宫内膜组织P4代谢率（59.1 ± 2.6%）显著高于D16或D19（44.0 ± 2.3%）（P<0.01）。子宫内膜组织产生的主要代谢产物为羟基化的SO -还原甾体，其中P4的SO -甾烷-3t，20 t-二醇和A的SO -雄甾烷-3 ′，17 ′-二醇最为显著。孕体组织则广泛代谢底物为5 β-还原型甾体化合物，从P4中鉴定出3 α-羟基-Sp-Spanan-20-酮和5 β-Spanan-3 o，20 o-二醇，从A中鉴定出3 β-羟基-5 β-雄甾烷- 17-酮和5 β-雄甾烷-3a，17 o-二醇。此外，A而不是P4的代谢导致产生少量（<200 pg）的雌酮和雌二醇-17 a。讨论了P4和A代谢产物的不同类型和代谢程度与奶牛生殖状况的关系。
A comparison was undertaken of the in vitro ability of two uterine -specific tissues, viz endo metrium and conceptus, to metabolize neutral steroids. Tissues were obtained at slaughter from 55 cows on Days (D) 16, 19, 23 and 27 postbreeding. D16 and D19 uteri which did not contain any products of conception were designated nonpregnant (NP); those bearing membranes, pregnant (P). Endometrial (500 mg) and conccptus (intact or halved) tissues (n-227) were incubated in minimal essential media (MEM) with 10 ng isotopically labeled progesterone (P4) or androstenedione (A). Extent of metabolism and qualitative appraisal of steroid metabolites were determined after extraction and separation through chromatographic columns before and after chemical conversion procedures. Identification and quantification of metabolites were verified by recrystallization to constant specific activity with authentic radioinert parent compounds. Both substrates were metabolized extensively by tissues, with more metabolism occurring in 3 than in 1 h (P<0.OO1). Endometrial tissue metabolized similar amounts of P4/mg tissue on D16 and D19 irrespective of reproductive status (P vs. NP) or the location of tissue within the uterus. However, D27 endometrial tissue metabolized more P4 (P<0.01) than that from D16 or D19 (59.1 ± 2.6% vs. 44.0 ± 2.3%) of pregnancy. Major metabolites produced by endometrial tissue were hydroxylated So -reduced steroids, most notably So -pregnane - 3t , 20t -diol from P4 and So -androstane - 3�, 1 7� -diol from A. In contrast, conceptus tissue metabolized sub strates extensively to 5p-reduced steroids, Identified were 3a-hydroxy-Sp-pregnan-20-one and 5$-pregnane- 3o, 20o-diol from P4 and 3ce-hydroxy-5�-androstan- 17-one and 5�-androstane3a, 17o-diol from A. In addition, metabolism of A but not P4 resulted in production of small quantities (<200 pg) of estrone and estradiol-17a. The implications of the differential types of metabolites and extents of metabolism of P4 and A are discussed in relation to reproductive status of the cow.