Fig 1. NO-cGMP signaling modulates hematopoiesis in vivo.

(A-E) NO upregulates erythropoiesis but suppresses myelopoiesis. Wild-type mice (n = 4) were treated with 8 ppm NO for 8 weeks. Intracellular cGMP levels of RBCs (A), peripheral blood leukocytes (B), total hemoglobin levels (C), hematocrit (D), and leukocyte count (E) were determined. P values are shown above the figures. (F-I) NO affects cell-lineage populations in BM. Mouse BMMNC, with or without 8 weeks of NO inhalation treatment, were examined for CD antigens. Results are shown for erythroid-lineage cells (F&G) and leukocytes (H&I). Experiments were repeated 3 times using BMMNCs from 3 defferent mice and representative results are shown. (J&K) NO affects cell differentiation of hematopoietic progenitors. Semi-solid colony assays were performed with BMMNC prepared from mice treated with 2 or 6 ppm NO for 8 weeks (J). The cells were plated on semi-solid plates with various SNP concentrations (K). The numbers of erythroid- (pink) and myeloid-lineage (blue) cells are shown. (L) NO donor upregulates βb-globin expression. Murine globin expression in erythroblasts prepared from semi-solid cultures was analyzed by immunoblotting. Cellular extracts (10 μg) were loaded to gels and murine βb-globin was detected by antibody.