Experimental investigation of erythropoietin-stimulated erythropoiesis under hypoxic conditions: A randomized controlled trial in a rodent model
Keywords:
Erythropoietin, EPO, red bloodAbstract
Background: Erythropoietin (EPO)-stimulated erythropoiesis under hypoxia is well-recognized, but the temporal dynamics and quantitative relationships between EPO exposure and red blood cell production under sustained hypoxic conditions remain incompletely characterized. Methods: This randomized controlled trial allocated 40 adult male Sprague-Dawley rats to normoxia (FiO₂ = 0.21, n=20) or sustained normobaric hypoxia (FiO₂ = 0.12, n=20) for 28 days. Serum EPO, complete blood counts, and reticulocyte percentages were measured at baseline, day 7, 14, 21, and 28. Results: Hypoxia induced rapid EPO elevation peaking at day 7 (80.15 ± 0.42 vs. 18.81 ± 0.08 pg/mL, p<0.001), followed by partial decline. RBC count and hemoglobin increased progressively from day 14, reaching 30% and 34% elevations at day 28, respectively (both p<0.001). Reticulocytes peaked at day 14 (8.48 ± 0.05%). Peak EPO strongly correlated with final RBC count (r=0.78, p<0.001). Conclusions: Sustained hypoxia produces a predictable, time-dependent erythropoietic response with peak EPO at day 7 preceding maximal RBC elevation by 14–21 days. Peak EPO predicts eventual erythropoietic magnitude, suggesting clinical utility for early response assessment in patients receiving erythropoiesis-stimulating agents.
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