title: Further evidence of the in vivo role of erythropoietin or companion molecules induced by hypoxia on proliferation and continuing differentiation of BFU-e in PCDC.
abstract: Normal and plethoric bone marrow cells were grown in plasma clot diffusion chambers (PCDC) implanted into the peritoneum of normal mice or mice submitted to 7 her of hypoxia (23,000 ft) daily, on a single day or on 2 consecutive days at different times after implantation of the PCDC's. Daily discontinuous hypoxia (DDH) produced more 6-day bursts than other treatments. Hypoxia on days 1 and 2 after implantation was nearly as effective as DDH on day-6 bursts. Later bouts of hypoxia or a singly hypoxic exposure on day 1 or 2 was less effective. Erythropoietin (Ep) levels were measured by bioassay on both diffusion chamber (DC) contents and serum. Serum Ep levels peaked at 160 mU/ml after a 7-hr hypoxic exposure while the DC content Ep levels were in the nondetectable range (less than 50 mU/ml). The data implies that either higher than normal Ep levels or a companion molecules (s) produced by hypoxia are required for 1-2 days early in the culture period of force an increasing number of BFU-d-e down the erythrocytic pathway and thus increase red cell production at times of need in vivo.
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells; D002454:Cell Differentiation; D002455:Cell Division; D002478:Cells, Cultured; D002999:Clone Cells; D004780:Environment, Controlled; D004912:Erythrocytes / Q000166:cytology*; D004921:Erythropoietin / Q000378:metabolism*; D000860:Hypoxia / Q000378:metabolism*; D008297:Male; D051379:Mice; D013997:Time Factors
chemical_list: D004921:Erythropoietin