PMID- 16185141
OWN - NLM
STAT- MEDLINE
DCOM- 20051216
LR  - 20181201
IS  - 1527-0297 (Print)
IS  - 1527-0297 (Linking)
VI  - 6
IP  - 3
DP  - 2005 Fall
TI  - Enhanced erythropoietin production during hypobaric hypoxia in mice under 
      treatments to keep the erythrocyte mass from rising: implications for the 
      adaptive role of polycythemia.
PG  - 238-46
AB  - Stress erythropoiesis is usually considered as a compensatory effort to 
      counteract tissue hypoxia. Its homeostatic importance in anemic hypoxia has not 
      been questioned, but researchers, clinicians, and mountain climbers have had 
      second thoughts on polycythemia as to its appropriateness for hypoxic or altitude 
      hypoxia (HA). Therefore, polycythemia, one of the responses to HA seen in 
      nongenetically adapted mammals, could or could not be considered beneficial. The 
      present study was thus performed to obtain further information on the importance 
      of HA polycythemia on acclimation of mice to HA. To this end, the development of 
      polycythemia was prevented by experimental manipulations (administration of 20 
      mg/kg/d of the hemolytic drug phenylhydrazine or removal of 0.225 mL/d of blood), 
      and the degree of tissue hypoxia was evaluated from plasma erythropoietin (pEPO) 
      concentration, as determined by immunoassay, in adult female mice exposed to air 
      maintained at 506 mbar (380 mmHg) in a simulated HA (SHA) chamber during at least 
      23.5 h/d for 9 d. Plasma EPO concentration in those treated hypoxic mice whose 
      hematocrit values remained almost unchanged was between 5.55 and 7.89 times 
      higher (depending on the experimental designs) than in control hypoxic mice 
      allowed to develop HA polycythemia. These results, plus the finding of an inverse 
      relationship between the hematocrit value and pEPO concentration in both the 
      polycythemic and normocythemic SHA-exposed mice indicate that HA polycythemia is 
      highly effective in ameliorating tissue hypoxia under SHA conditions, thus giving 
      support to the concept of the important role of the increased hemoglobin mass in 
      nongenetically adapted animals, whereas a left-shifted oxyhemoglobin dissociation 
      curve confers a good degree of adaptation to HA in genetically adapted animals.
FAU - Bozzini, Carlos E
AU  - Bozzini CE
AD  - Department of Physiology, Faculty of Odontology, University of Buenos Aires, 
      Argentina. cebozi@fisio.odon.uba.ar
FAU - Barcelo, Ana C
AU  - Barcelo AC
FAU - Conti, Maria I
AU  - Conti MI
FAU - Martinez, Maria P
AU  - Martinez MP
FAU - Alippi, Rosa M
AU  - Alippi RM
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - High Alt Med Biol
JT  - High altitude medicine & biology
JID - 100901183
RN  - 0 (Phenylhydrazines)
RN  - 064F424C9K (phenylhydrazine)
RN  - 11096-26-7 (Erythropoietin)
SB  - IM
MH  - Altitude Sickness/*blood
MH  - Analysis of Variance
MH  - Animals
MH  - Atmosphere Exposure Chambers
MH  - Atmospheric Pressure
MH  - Cell Hypoxia/drug effects/physiology
MH  - Erythropoiesis/*drug effects
MH  - Erythropoietin/*biosynthesis/blood/metabolism
MH  - Female
MH  - Hematocrit
MH  - Immunoassay
MH  - Mice
MH  - Phenylhydrazines/*pharmacology
MH  - Polycythemia/*metabolism
MH  - Secretory Rate/drug effects
EDAT- 2005/09/28 09:00
MHDA- 2005/12/17 09:00
CRDT- 2005/09/28 09:00
PHST- 2005/09/28 09:00 [pubmed]
PHST- 2005/12/17 09:00 [medline]
PHST- 2005/09/28 09:00 [entrez]
AID - 10.1089/ham.2005.6.238 [doi]
PST - ppublish
SO  - High Alt Med Biol. 2005 Fall;6(3):238-46. doi: 10.1089/ham.2005.6.238.