Pakistan Journal of Biological Sciences1028-88801812-5735Asian Network for Scientific Information10.3923/pjbs.2010.185.189YousefiB. SameneH. R.42010134This study was planned to determine the effects of All-Trans Retinoic Acid (ATRA) on the progenitors of White Blood Cells (WBC) and survey their outcomes in rat's embryo during both late-yolk sac and fetal liver stages of hematopoiesis. Single oral dose (100 mg kg-1) of ATRA was administered to rat on Gestation Day (GD) 10 and fetuses were observed on GD 18. The fetus's blood (from experimental group and control each, n = 24) were obtained directly from heart, as placental and mother circulation was continued and subsequently processed for Giemsa staining and followed by WBC counting and measuring. Statistical analysis was made by student t-test. A p-value<0.05 was considered significant. In the experimental embryos on GD 18, the mean number of WBC (29.2%), neutrophil, lymphocyte and monocyte were increased. There was a significant difference in WBC (p<0.0001) and neutrophil (p<0.001) between the groups in this regard. The mean diameter of neutrophil, lymphocyte and monocyte were compared in two groups. The results showed no significant change on experimental and control groups. We concluded that ATRA may have positive effects on proliferation, differentiation and maturation of neutrophil without having any significant effects on the diameter of cells throughout normal granulocyte differentiation in embryo during both late-yolk sac and fetal liver stages of hematopoiesis.]]>Mozdarani, H., S. Akhlaghpoor, A.A. Pourfatollah, M. Soleimani and A.A.M. Akbari,2007+ cells in mouse bone marrow using clinical MR imaging.]]>10833842Bedi, A. and S.J. Sharkis,199521221Chen, X., R.S. Welner and P.W. Kincade,20093925152524Collins, S.J., J. Ulmer, L.E. Purton and G. Darlington,20019823822388Douer, D. and H.P. Koeffler,1982in vitro.]]>6910391041Hafen, E. and H. Stocker,20031E86E86Iwata, M., Y. Eshima and H. Kagechika,20031510171025Kang, S.G., H.W. Lim, O.M. Andrisani, H.E. Broxmeyer and C.H. Kim,2007+ regulatory T cells.]]>17937243733Kastner, P., H.J. Lawrence, C. Waltzinger, N.B. Ghyselinck, P. Chambon and S. Chan,20019713141320Kingsley, P.D., J. Malik, K.A. Fantauzzo and J. Palis,20041041925Kinoshita, T., K. Koike, H.H. Mwamtemi, S. Ito and S. Ishida et al.,20009528212828Labbaye, C., M. Valtieri, U. Testa, A. Giampaolo and E. Meccia et al.,1994GATA1 expression in purified adult-progenitor culture.]]>83651656Labrecque, J., D. Allan, P. Chambon, N.N. Iscove, D. Lohnes and T. Hoang,1998in vitro in hematopoietic cells lacking retinoic acid receptors alpha1 and gamma.]]>92607615Lanotte, M., V. Martin-Thouvenin, S. Najman, P. Balerini, F. Valensi and R. Berger,19917710801086Lawson, N.D. and N. Berliner,19992713551367Le-Guyader, D., M.J. Redd, E .Colucci-Guyon, E. Murayama and K. Kissa et al.,2008111132141Leelasiri, A., T. Numbenjapol, W. Prayoonwiwat, W. Mongkolsritrakul and C. Srisawat,200588302310Mohammadi, S.S., E. Shahbazian, G. Shoeibi and F. Almassi,200912603606Padmanabhan, R.,199812139151Palis, J., S. Robertson, M. Kennedy, C. Wall and G. Keller,199912650735084Paul, C.C., S. Mahrer, M. Tolbert, B.L. Elbert and I. Wong et al.,19958637373744Rupes, I.,200218479485Seguin-Devaux, C., D. Hanriot, M. Dailloux, V. Latger-Cannard and F. Zannad et al.,20052456776Stosic-Grujicic, S. and L. Ejdus,1994in vitro T cell alloreactivity by synthetic retinoids.]]>278792Tashiro, S., A. Sedohara, M. Asashima, Y. Izutsu and M. Maeno,2006Xenopus laevis embryo.]]>48499512Tobler, A., M.I. Dawson and H.P. Koeffler,1986in vitro.]]>78303309Tocci, A., I. Parolini, M. Gabbianelli, U. Testa and L. Luchetti et al.,19968828782888Valtieri, M., G. Boccoli, U. Testa, C. Barletta and C. Peschle,19917718041812Warrell, R.P., S.R.J. Frankel, W.H.J. Miller, D.A. Scheinberg and L.M. Itri et al.,199132413851393Buitenhuis, M., L.P. Verhagen, H.W. van Deutekom, A. Castor and S. Verploegen et al.,2008111112121