Trahair J F, Perry R A, Silver M, Robinson P M
Q J Exp Physiol. 1987 Jan;72(1):71-9. doi: 10.1113/expphysiol.1987.sp003056.
The effect of cortisol on small intestinal maturation was investigated in catheterized fetal sheep by infusing 2 mg cortisol/d between 105 and 115 d gestation (term ca. 147 d). This treatment resulted in a fivefold increase in plasma cortisol compared with catheterized control fetuses of the same age. There were no detectable changes in enterocyte morphology after the cortisol infusion; the size and density of most intestinal components were largely unaffected by the treatment. By contrast, the kinetics of the enterocyte population were significantly altered by the raised cortisol levels. The proportion of crypt cells labelled was significantly increased from 0.20 +/- 0.04 to 0.33 +/- 0.03 in the proximal region (P less than 0.01) and from 0.22 +/- 0.03 to 0.31 +/- 0.02 in the distal region (P less than 0.01). The migration of enterocytes in both regions was significantly increased to nearly twice the control values (P less than 0.05). Correspondingly, renewal time was almost halved in both regions, while cell density was unchanged in distal and decreased in proximal regions. Hence cell loss appeared to have increased as a result of the cortisol infusion. The kinetic parameters for the villus enterocyte population of the fetuses receiving cortisol before 115 d were of similar magnitude to those previously seen in the normal near-term fetus. To this extent exogenous cortisol treatment given before a pre-partum surge mimicked the action of the endogenous hormone in late gestation.
通过在妊娠105至115天（足月约147天）期间每天向插入导管的胎羊输注2毫克皮质醇，研究了皮质醇对小肠成熟的影响。与相同年龄的插入导管的对照胎儿相比，这种处理使血浆皮质醇增加了五倍。输注皮质醇后，肠上皮细胞形态没有可检测到的变化；大多数肠道成分的大小和密度在很大程度上不受该处理的影响。相比之下，升高的皮质醇水平显著改变了肠上皮细胞群体的动力学。在近端区域，标记的隐窝细胞比例从0.20±0.04显著增加到0.33±0.03（P<0.01），在远端区域从0.22±0.03增加到0.31±0.02（P<0.01）。两个区域的肠上皮细胞迁移均显著增加，几乎是对照值的两倍（P<0.05）。相应地，两个区域的更新时间几乎减半，而远端区域的细胞密度不变，近端区域的细胞密度降低。因此，由于输注皮质醇，细胞损失似乎增加了。在115天之前接受皮质醇治疗的胎儿的绒毛肠上皮细胞群体的动力学参数与之前在正常近足月胎儿中观察到的参数相似。在这个程度上，在产前激增之前给予外源性皮质醇治疗模拟了内源性激素在妊娠后期的作用。
