Erythropoietic Response to Hypoxia as a Function of Age in the Normal Male Rat

Abstract

The labeled red cell volume technique was used to determine the erythropoietic response to an hypoxic stimulus in groups of male rats of various ages from 5 to 250 days. Whereas rats of 50 days of age or older responded well erythropoietically to the hypoxic stimulus, rats of 5–30 days of age show no statistical increase in total red cell volume or total hemoglobin when exposed to this stimulus. The inability of the young rat to respond to an hypoxic stimulus is here given as evidence of the high rate of red cell production existing in this animal. Further, it is postulated that the relative daily red cell production in these young animals is at a maximal or near maximal level.