Submitted to: Journal of Federation of American Societies for Experimental Biology
Publication Type: Abstract Only
Publication Acceptance Date: 12/2/2002
Publication Date: 3/14/2003
Citation: Reeves, P.G., Ralston, N.V.C., Idso, J.P., Lukaski, H.C. 2003. Dietary Cu-Fe-amino acid interactions: flow cytometry of rat hematology indices [abstract]. The Federation of American Societies of Experimental Biology Journal 17:A1128.
Technical Abstract: We used high-precision flow cytometry (FC) to assess the hypochromic, microcytic anemia that occurs in Cu and Fe deficiency (CuD; FeD). The method allowed simultaneous and quantitative evaluation of RBC and platelet (PLT) size and RNA content. The experimental design was a 2x2x2 factorial with 6 and <1 ppm dietary Cu and 35 and 10 ppm Fe. Because dietary sulfur amino acids (SAA) can affect Cu indices, the third factor was either L-methionine (MET) or L-cystine as the main SAA source. The diets were fed to weanling male rats (16/trt) for 6 wk. RBC and PLT indices were assessed in EDTA treated blood by FC and with a hematology analyzer. Reticulocyte count and RNA content were determined by Thiazole Orange. FeD had little effect on RBC number, unless the rats also were CuD. RBC number was lower in MET fed rats, but only if Cu was low. RBC volume was reduced in both FeD and CuD. As in previous studies, the hematology analyzer showed an apparent increase in PLT size and number in CuD or FeD rats, but the FC showed no change in these parameters; the analyzer produced an apparent artifact by counting the microcytic RBC's as PLT. Reticulocytes were smaller in both FeD and CuD than controls, and their number was elevated in both deficiencies, but more so in FeD; the effect of CuD and FeD together was additive. Unexpectedly, PLT RNA content increased substantially in CuD or FeD, perhaps as the result of increased turnover. Integrated analysis of blood indices using FC to augment hematology analysis provides greater insight into hematopoietic defects of CuD or FeD than has been observed before.