Okabe J, Tajima S, Yamato O, Inaba M, Hagiwara S, Maede Y
Department of Veterinary Clinical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
J Vet Med Sci. 1996 Jul;58(7):629-34. doi: 10.1292/jvms.58.629.
The pathogenesis of poikilocytosis in calves was investigated. Nine calves 1 to 2 months old exhibiting poikilocytosis (poikilocytic calves), were examined. The proportion of poikilocytes in their blood was more than 70% in two calves (severely poikilocytic), while it averaged 30% in the remaining seven calves (moderately poikilocytic). All of the polikilocytic calves exhibited mild anemia. The concentration of plasma iron in 8 of them was 20-30% of that in normal calves, but it increased as the calves aged. The polikilocyte count in moderately poikilocytic calves decreased in proportion to the increase of the plasma iron concentration, though a high poikilocyte count was observed in a severely poikilocytic calf even after the plasma iron concentration reached the normal level. Column chromatography of a hemoglobin preparation from all the calves examined revealed 5 distinct peaks. Three peaks were embryonic, fetal and adult hemoglobins, respectively. The other peaks were tentatively designated Hb-2 and Hb-3, respectively. The amount of Hb-2 in the two severely poikilocytic calves was about three times that in the other calves including those moderately poikilocytic, and it decreased as the calves aged. The decrease of Hb-2 in one severely poikilocytic calf was related to a reduction of the proportion of poikilocytes in its peripheral blood. There was no significant difference in age-dependent changes of hemoglobin types between moderately poikilocytic calves and normal calves. Furthermore, SDS-PAGE analysis of red cell membrane revealed that protein 4.2 consisted of two polypeptides in the two severely poikilocytic, and three moderately poikilocytic calves, while it consisted of a single polypeptide in the remaining calves examined. These results indicated that the abnormalities of hemoglobin composition and protein 4.2 in the erythrocyte membrane observed in the severely poikilocytic calves might be responsible for the morphological changes in the erythrocytes, whereas iron deficiency was thought to be the predominant cause of poikilocytosis in the moderately poikilocytic calves.
对犊牛异形红细胞增多症的发病机制进行了研究。检查了9头1至2月龄出现异形红细胞增多症的犊牛（异形红细胞增多症犊牛）。其中2头犊牛血液中异形红细胞的比例超过70%（重度异形红细胞增多症），其余7头犊牛平均为30%（中度异形红细胞增多症）。所有异形红细胞增多症犊牛均表现出轻度贫血。其中8头犊牛的血浆铁浓度为正常犊牛的20%-30%，但随着犊牛年龄增长而升高。中度异形红细胞增多症犊牛的异形红细胞计数与血浆铁浓度的升高成比例下降，不过在一头重度异形红细胞增多症犊牛中，即使血浆铁浓度达到正常水平后仍观察到较高的异形红细胞计数。对所有检查犊牛的血红蛋白制剂进行柱层析显示有5个明显的峰。三个峰分别为胚胎血红蛋白、胎儿血红蛋白和成人血红蛋白。另外两个峰分别暂定为Hb-2和Hb-3。两头重度异形红细胞增多症犊牛中Hb-2的含量约为其他犊牛（包括中度异形红细胞增多症犊牛）的三倍，且随着犊牛年龄增长而减少。一头重度异形红细胞增多症犊牛中Hb-2的减少与外周血中异形红细胞比例的降低有关。中度异形红细胞增多症犊牛和正常犊牛之间血红蛋白类型的年龄依赖性变化没有显著差异。此外，红细胞膜的SDS-PAGE分析显示，在两头重度异形红细胞增多症犊牛和三头中度异形红细胞增多症犊牛中，蛋白4.2由两条多肽组成，而在其余检查的犊牛中由一条多肽组成。这些结果表明，重度异形红细胞增多症犊牛中观察到的红细胞膜血红蛋白组成和蛋白4.2的异常可能是红细胞形态变化的原因，而缺铁被认为是中度异形红细胞增多症犊牛异形红细胞增多症的主要原因。
