Bolin Greta, Dubansky Benjamin, Burggren Warren W
Developmental Integrative Biology Research Group, Department of Biological Sciences, University of North Texas, 1155 Union Circle #305220, Denton, TX 76203-5017, USA.
Developmental Integrative Biology Research Group, Department of Biological Sciences, University of North Texas, 1155 Union Circle #305220, Denton, TX 76203-5017, USA.
Comp Biochem Physiol A Mol Integr Physiol. 2017 Feb;204:185-196. doi: 10.1016/j.cbpa.2016.11.016. Epub 2016 Nov 26.
The metanephric kidneys of the chicken embryo, along with the chorioallantoic membrane, process water and ions to maintain osmoregulatory homeostasis. We hypothesized that changes in relative humidity (RH) and thus osmotic conditions during embryogenesis would alter the developmental trajectory of embryonic kidney function. White leghorn chicken eggs were incubated at one of 25-30% relative humidity, 55-60% relative humidity, and 85-90% relative humidity. Embryos were sampled at days 10, 12, 14, 16, and 18 to examine embryo and kidney mass, glomerular characteristics, body fluid osmolalities, hematological properties, and whole embryo oxygen consumption. Low and especially high RH elevated mortality, which was reflected in a 10-20% lower embryo mass on D18. Low RH altered several glomerular characteristics by day 18, including increased numbers of glomeruli per kidney, increased glomerular perfusion, and increased total glomerular volume, all indicating potentially increased functional kidney capacity. Hematological variables and plasma and amniotic fluid osmolalities remained within normal physiological values. However, the allantoic, amniotic and cloacal fluids had a significant increase in osmolality at most developmental points sampled. Embryonic oxygen consumption increased relative to control at both low and high relative humidities on Day 18, reflecting the increased metabolic costs of osmotic stress. Major differences in both renal structure and performance associated with changes in incubation humidity occurred after establishment of the metanephric kidney and persisted into late development, and likely into the postnatal period. These data indicate that the avian embryo deserves to be further investigated as a promising model for fetal programming of osmoregulatory function, and renal remodeling during osmotic stress.
鸡胚的后肾以及尿囊绒膜处理水和离子以维持渗透调节稳态。我们假设胚胎发育过程中相对湿度（RH）的变化以及由此产生的渗透条件会改变胚胎肾功能的发育轨迹。白来航鸡蛋在25 - 30%相对湿度、55 - 60%相对湿度和85 - 90%相对湿度之一的条件下孵化。在第10、12、14、16和18天对胚胎进行取样，以检查胚胎和肾脏质量、肾小球特征、体液渗透压、血液学特性以及全胚胎耗氧量。低湿度尤其是高湿度会提高死亡率，这在第18天胚胎质量降低10 - 20%中得到体现。到第18天，低湿度改变了几个肾小球特征，包括每个肾脏肾小球数量增加、肾小球灌注增加以及肾小球总体积增加，所有这些都表明肾脏功能容量可能增加。血液学变量以及血浆和羊水渗透压保持在正常生理值范围内。然而，在大多数取样的发育阶段，尿囊液、羊水和泄殖腔液的渗透压显著增加。在第18天，低湿度和高湿度条件下胚胎耗氧量相对于对照组均增加，这反映了渗透应激增加的代谢成本。与孵化湿度变化相关的肾脏结构和性能的主要差异在后肾形成后出现，并持续到发育后期，可能还会持续到出生后阶段。这些数据表明，鸟类胚胎作为渗透调节功能胎儿编程和渗透应激期间肾脏重塑的一个有前景的模型值得进一步研究。
