Metabolism of glycated proteins in the rabbit. 3. The glycated hemoglobin levels and the changes in fetal hemoglobin after births

In the domestic animals and Ln humans, the non-enzymatic glycosylation of t he p chains of the adult hemoglobin (HbA) (alpha (2)beta (2)), resulting in the formation of so-called glycated hemoglobin (GHb) (HbA(1C) subfraction) is a good background blood plasma glucose mirror. This is an indicator of the carbohydrate/energy metabolism, reliably showing the elevated (widely u sed for humane diabetes diagnosis) and also decreased (energy deficiency, e .g. ketosis of the cow) blood glucose levels of the adults in the past. Thi s connection has been proved also in adult rabbits (15, 17, 18). However, the high HbF amount (alpha (2)gamma (2)) after birth with very low glycosylation ability of the gamma chains may be the reason for the lower GHb levels in human newborns and newborn calves, than that of the adults (1 , 2, 4, 9, 10, 12, 20). The authors' aim was to determine the GHb % values also in newborn and youn g rabbits, in connection with the changes in HbF and HbA content of the red blood cells. blood samples were taken from New-Zealand white rabbits at bi rth (0th day), and on the 1st, 2nd, 7th, 14th 28th, 31st, 35th, 46th, 56th and 70th days of life. The specific human staining method of NIERHAUS and BETKE (1968) (12) was mo dified by the authors earlier to differentiate the adult and fetal Hb conta ining red blood cells of the calves (LAKNER et al., 2001) (9). These modifi cations were the followings: fixation of blood smear in 80% ethyl alcohol, for elution: HCl FeCl3 and hematoxylin, staining with erythrosin. This meth od was applied also for the staining and evaluation of the blood smears of the young rabbits. The cytologic results (Figures 1) are presented in the Table and Figure 2 I t has been found, that between the 2nd -7th days of Life the 50% of HbF cha nges to HbA At about the 31st day of life, HbF nearly totally disappeares f rom the blood of young rabbits. These shorter time-of pel-lodes, than those of the calves (9) can be explained with the similarly shorter lifetime of the red blood cells of the rabbit (3, 7, 19). The changes in GHb% follow the alterations of the red blood cells: its leve l showes a continuous and significant (p <0.001) increase from a low value (<2.50%), till it nearly reaches (4.10%) the range of the adult rabbits (15 ) to the 10th weeks of life.