The effect of hypoxia on red blood cells of flounder: a morphologic and autoradiographic study

Flounders were maintained in water with low oxygen content (2.6–2.7 mg 1 ^{- 1}, 30% saturation) for 2, 6 and 24 h. Hypoxia enhanced the proliferation and differentiation process among juvenile red blood cells (RBCs) in the pronephros. It was accompanied by an increase in RBCs number in blood by up to 37% (P<0.01) 6 h after adaptation. The number of dividing mature RBCs in blood during the initial period of adaptation (2 h) was 2.5 times greater (P<0.001) than in the control group. It was shown ( in vitro ) that the serum contained factors stimulating division of mature RBCs in blood during adaptation to hypoxia.