Erythropoietin production in exhypoxic polycythemic mice

Our present study was undertaken to determine the serum erythropoietin concentration (radioimmunoassay), hematocrit, red cell mass, and body weight of mice exposed to hypoxia in a hypobaric chamber (0.42 atm, 22 h/day) for 14 days and during the 10 posthypoxic days at ambient pressure to clarify the correlation of the red cell mass and erythropoietin production during hypoxia. The mean serum erythropoietin titer was 326.23 +/- 77.04 mU/ml after 2 days, reached the highest level after 3 days (452.2 +/- 114.5 mU/ml), then gradually declined to a level of 36.5 +/- 11.4 mU/ml after 14 days of hypoxia, and was undetectable during the 10-day posthypoxic period. The hematocrit values were significantly increased from 41.09 +/- 0.50% at day 0 to 51.65 +/- 1.08% after 3 days and to 72.20 +/- 1.53% after 14 days of hypoxia. The red cell mass (calculated from initial body weight) increased from 3.24 +/- 0.1 ml/100 g at day 0 to 7.32 +/- 0.46 ml/100 g after 14 days of hypoxia and declined to 6.66 +/- 0.53 ml/100 g at the end of the 10-day posthypoxic period. The mice lost weight while they were in the hypobaric chamber and showed a significant increase in body weight during the 10-day posthypoxic period. These studies support the concept that chronic intermittent hypoxia causes an early increase, followed by a rapid decline, in erythropoietin production, which is correlated with the gradual increase in red cell mass.

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Analysis of Red Cell Mass and Plasma Volume in Patients With Polycythemia

Archives of Pathology & Laboratory Medicine ◽

10.5858/2005-129-89-aorcma ◽

2005 ◽

Vol 129 (1) ◽

pp. 89-91 ◽

Cited By ~ 2

Author(s):

Mordechai Lorberboym ◽

Naomi Rahimi-Levene ◽

Helena Lipszyc ◽

Chun K. Kim

Keyword(s):

Body Weight ◽

Plasma Volume ◽

Cell Mass ◽

Mean Value ◽

Whole Body ◽

Red Cell ◽

Volume Data ◽

Red Cell Mass ◽

The Mean ◽

Iodine 125

Abstract Context.—Polycythemia describes an increased proportion of red blood cells in the peripheral blood. In absolute polycythemia, there is increased red cell mass (RCM) with normal plasma volume, in contrast with apparent polycythemia, in which there is increased or normal RCM and decreased plasma volume. In order to deliver the appropriate treatment it is necessary to differentiate between the two. Objective.—A retrospective analysis of RCM and plasma volume data are presented, with special attention to different methods of RCM interpretation. Design.—The measurements of RCM and plasma volume in 64 patients were compared with the venous and whole-body packed cell volume, and the incidence of absolute and apparent polycythemia was determined for increasing hematocrit levels. Measurements of RCM and plasma volume were performed using chromium 51–labeled red cells and iodine 125–labeled albumin, respectively. The measured RCM of each patient was expressed as a percentage of the mean expected RCM and was also defined as being within or outside the range of 2 SD of the mean. The results were also expressed in the traditional manner of mL/kg body weight. Results.—Twenty-one patients (13 women and 8 men) had absolute polycythemia. None of them had an increased plasma volume beyond 2 SD of the mean. When expressed according to the criteria of mL/kg body weight, 17 of the 21 patients had abnormally increased RCM, but 4 patients (19%) had a normal RCM value. Twenty-eight patients had apparent polycythemia. The remaining 15 patients had normal RCM and plasma volume. Conclusions.—The measurement of RCM and plasma volume is a simple and necessary procedure in the evaluation of polycythemia. In obese patients, the expression of RCM in mL/kg body weight lacks precision, considering that adipose tissue is hypovascular. The results of RCM are best described as being within or beyond 2 SD of the mean value.

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Polycythemia in rats following restricted food intake

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1964.206.4.762 ◽

1964 ◽

Vol 206 (4) ◽

pp. 762-764 ◽

Cited By ~ 1

Author(s):

Herbert Wohl ◽

Clarence Merskey

Keyword(s):

Body Weight ◽

Food Intake ◽

Cell Mass ◽

Diet Group ◽

Control Group ◽

Red Cell ◽

Restricted Diet ◽

Red Cell Mass ◽

Normal Chow ◽

Unit Body Weight

Rats were divided into two groups such that mean weight and hemoglobin and hematocrit levels were not significantly different. One group (controls) was then fed a normal chow ad libitum. The other group was fed 6 g daily (30% of normal intake) for 2 weeks. The hemoglobin levels of rats fed the restricted diet rose 1.4–3.5 g/100 ml and hematocrit level rose 2–6%. At the end of 2 weeks total red cell mass (Cr51) was 5.5–6.0 ml in the underfed groups compared with 6.8 ml in the control group. Body weight fell proportionally more than did red cell mass, elevating the calculated red cell mass per unit body weight. Serum osmolality and K+ were not significantly different from control values, and there was a slightly higher serum Na+ and Cl– in the restricted diet group. It is concluded that restriction of food intake produced a relative polycythemia. At the end of 2 weeks of restriction an isosmotic reduction in plasma volume was present.

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Erythropoietin-dependent primary pure erythrocytosis

Blood ◽

10.1182/blood.v53.6.1076.1076 ◽

1979 ◽

Vol 53 (6) ◽

pp. 1076-1084 ◽

Cited By ~ 28

Author(s):

N Dainiak ◽

R Hoffman ◽

AI Lebowitz ◽

L Solomon ◽

L Maffei ◽

...

Keyword(s):

Bone Marrow ◽

Polycythemia Vera ◽

Colony Formation ◽

Bone Marrow Cells ◽

Cell Mass ◽

Red Cell ◽

Extensive Search ◽

Erythropoietin Production ◽

Red Cell Mass ◽

Marrow Cells

Abstract We investigated the pathogenesis of isolated erythrocytosis of 14 yr duration in a 28-yr-old man. The increase in red cell mass was attributed to increased erythropoietin production. An extensive search for recognized causes of secondary erythrocytosis was unrevealing. Family members were found to be hematologically normal. After reduction of the circulating red cell mass by 20%, erythropoietin activity nearly quadrupled, thus suggesting a normal erythropoietin response to phlebotomy. When bone marrow cells of the patient were cultured in plasma clots in the absence of added erythropoietin, endogenous erythroid colony formation was observed, a pattern previously believed to be specific for polycythemia vera bone marrow cells. Our observations suggest that the erythrocytosis in this individual is best explained by an abnormal “servoregulatory” mechanism of erythropoietin production. In addition, this is the first instance in which the rule that endogenous erythroid colony formation is correlated with the diagnosis of polycythemia vera has not held.

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Revisiting Diagnostic performances of serum erythropoïetin level and JAK2 mutation for polycythemias: analysis of a cohort of 1090 patients with red cell mass measurement

British Journal of Haematology ◽

10.1111/bjh.17848 ◽

2021 ◽

Author(s):

Nabih Maslah ◽

Odonchimeg Ravdan ◽

Louis Drevon ◽

Emmanuelle Verger ◽

Célia Belkhodja ◽

...

Keyword(s):

Mass Measurement ◽

Cell Mass ◽

Red Cell ◽

Jak2 Mutation ◽

Serum Erythropoietin Level ◽

Red Cell Mass ◽

Serum Erythropoietin ◽

Erythropoietin Level

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THE EVALUATION OF BLOOD VOLUME AND TOTAL RED CELL MASS AS PREDICTORS OF GROSS BODY COMPOSITION IN THE PIG

Canadian Journal of Animal Science ◽

10.4141/cjas65-035 ◽

1965 ◽

Vol 45 (3) ◽

pp. 203-210 ◽

Cited By ~ 7

Author(s):

H. Doornenbal ◽

A. H. Martin

Keyword(s):

Body Composition ◽

Body Weight ◽

Blood Volume ◽

Total Protein ◽

Cell Mass ◽

Red Cell ◽

Body Protein ◽

Weight Range ◽

Red Cell Mass ◽

Total Body

In a study of growth and development patterns in the pig, data were obtained on body weight, total body protein, blood volume, and red cell mass for a total of 88 pigs, ranging in live weight from 9 to 103 kg. The relationships of total body protein to the other variables were analyzed by multiple regression techniques on both an overall and stratified basis. Over the entire weight range, body weight itself explained 98% of the variability in total protein. When the analysis was restricted to pigs in the weight range of 81–103 kg the contribution of body weight in predicting total protein decreased considerably (50%), with concomitant increase in predictive value of blood volume (8%). It was concluded that blood volume and similar physiological measurements could be of major importance in predicting body composition in market weight pigs.

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Feedback Regulation by Red Cell Mass of the Sensitivity of the Erythropoietin-producing Organ to Hypoxia

Blood ◽

10.1182/blood.v36.6.754.754 ◽

1970 ◽

Vol 36 (6) ◽

pp. 754-763 ◽

Cited By ~ 14

Author(s):

E. NECčAS ◽

J. NEUWIRT

Keyword(s):

Hyperbaric Oxygen ◽

Feedback Inhibition ◽

Cell Mass ◽

Feedback Regulation ◽

Red Cell ◽

Short Intervals ◽

Erythropoietin Production ◽

Red Cell Mass ◽

Different Types

Abstract The effects of short intervals of anemic, hypoxic and CO hypoxia of various degrees on erythropoietin production have been compared in anemic, normal and polycythemic rats. The anemic and CO hypoxia were terminated by the exposure of rats to hyperbaric oxygen. The duration of hypoxic periods of different types of hypoxia ranged from 15 to 120 minutes. The decreased response of erythropoietin production to hypoxia was observed in rats having higher hematocrit. It is assumed that there is feedback inhibition, by the circulating red cell mass, of the sensitivity of the erythropoietin-producing organ to hypoxia.

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Erythropoietin-dependent primary pure erythrocytosis

Blood ◽

10.1182/blood.v53.6.1076.bloodjournal5361076 ◽

1979 ◽

Vol 53 (6) ◽

pp. 1076-1084 ◽

Cited By ~ 1

Author(s):

N Dainiak ◽

R Hoffman ◽

AI Lebowitz ◽

L Solomon ◽

L Maffei ◽

...

Keyword(s):

Bone Marrow ◽

Polycythemia Vera ◽

Colony Formation ◽

Bone Marrow Cells ◽

Cell Mass ◽

Red Cell ◽

Extensive Search ◽

Erythropoietin Production ◽

Red Cell Mass ◽

Marrow Cells

We investigated the pathogenesis of isolated erythrocytosis of 14 yr duration in a 28-yr-old man. The increase in red cell mass was attributed to increased erythropoietin production. An extensive search for recognized causes of secondary erythrocytosis was unrevealing. Family members were found to be hematologically normal. After reduction of the circulating red cell mass by 20%, erythropoietin activity nearly quadrupled, thus suggesting a normal erythropoietin response to phlebotomy. When bone marrow cells of the patient were cultured in plasma clots in the absence of added erythropoietin, endogenous erythroid colony formation was observed, a pattern previously believed to be specific for polycythemia vera bone marrow cells. Our observations suggest that the erythrocytosis in this individual is best explained by an abnormal “servoregulatory” mechanism of erythropoietin production. In addition, this is the first instance in which the rule that endogenous erythroid colony formation is correlated with the diagnosis of polycythemia vera has not held.

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