Department of Biological Sciences, University of North Texas, 1155 Union Circle #305220, Denton, TX 76203, USA.
Comp Biochem Physiol A Mol Integr Physiol. 2011 Jul;159(3):225-33. doi: 10.1016/j.cbpa.2011.02.024. Epub 2011 Mar 3.
Oxygen demand increases during embryonic development, requiring an increase in red blood cells (RBCs) containing hemoglobin (Hb) to transport O(2) between the respiratory organ and systemic tissues. A thorough ontogenetic understanding of the onset and maturation of the complex regulatory processes for RBC concentration ([RBC]), Hb concentration ([Hb]), hematocrit (Hct), mean corpuscular indices (mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration ([MCHb])) is currently lacking. We hypothesize that during the last half of incubation when the respiratory organ (the chorioallantoic membrane) envelops most of the egg contents, mean corpuscular indices will stabilize. Accordingly, Hct, [RBC] and [Hb] must also all change proportionally across development. Further, we hypothesize that the hematological respiratory variables develop and mature as a function of incubation duration, independently of embryonic growth. As predicted, a similar increase in Hct (from 18.7±0.6% on day 10 (d10) to 34.1±0.5% on d19 of incubation), [RBC] (1.13±0.03×10(6)/μL to 2.50±0.03×10(6)/μL) and [Hb] (6.1±0.2 g% to 11.2±0.1 g%) occurred during d10-19. Both [RBC] and [Hb] demonstrated high linear correlation with Hct, resulting in constant [MCHb] (33 g% from d10 to d19). The decrease in MCV (from ~165 μ(3) on d10 to ~140 μ(3) on d13) and MCH (55 pg to 45 pg) during d10-13, may be attributed to a changeover from larger primary to smaller secondary and adult-type erythrocytes with MCV and MCH remaining constant (140 μ(3) and ~45 pg respectively) for the rest of the incubation period (d13-19). Hematological respiratory values on a given incubation day were identical between embryos of different masses using either natural mass variation or experimental growth acceleration, indicating that the hematological variables develop as a function of incubation time, irrespective of embryo growth.
胚胎发育过程中氧气需求增加，需要增加含有血红蛋白 (Hb) 的红细胞 (RBC)，以便在呼吸器官和全身组织之间运输氧气。目前，人们对 RBC 浓度 ([RBC])、Hb 浓度 ([Hb])、血细胞比容 (Hct)、平均红细胞指数（平均红细胞体积 (MCV)、平均红细胞血红蛋白 (MCH) 和平均红细胞血红蛋白浓度 ([MCHb])) 的复杂调节过程的发生和成熟还没有全面的了解。我们假设，在孵化的最后一半，当呼吸器官（绒毛尿囊膜）包裹大部分卵内容物时，平均红细胞指数将稳定下来。因此，Hct、[RBC] 和 [Hb] 在整个发育过程中也必须按比例变化。此外，我们假设血液学呼吸变量的发展和成熟是孵化时间的函数，与胚胎生长无关。正如预测的那样，Hct（从孵化第 10 天的 18.7±0.6%增加到第 19 天的 34.1±0.5%）、[RBC]（1.13±0.03×10(6)/μL 增加到 2.50±0.03×10(6)/μL）和 [Hb]（6.1±0.2 g%增加到 11.2±0.1 g%）在第 10 天至第 19 天期间均呈相似的增加。[RBC] 和 [Hb] 与 Hct 呈高度线性相关，导致 [MCHb] 保持不变（从第 10 天到第 19 天约为 33 g%）。在第 10 天至第 13 天期间，MCV（从约 165 μ(3)减少到约 140 μ(3)）和 MCH（从 55 pg 减少到 45 pg）的减少可能归因于从较大的原红细胞到较小的次红细胞和成人型红细胞的转换，MCV 和 MCH 在整个孵化期间保持不变（分别约为 140 μ(3)和 45 pg）（第 13 天至第 19 天）。在给定的孵化日，使用自然质量变化或实验生长加速，不同质量的胚胎之间的血液学呼吸值是相同的，这表明血液学变量是作为孵化时间的函数而发展的，而与胚胎生长无关。
