Polycythemia in rats following restricted food intake

1964 ◽  
Vol 206 (4) ◽  
pp. 762-764 ◽  
Author(s):  
Herbert Wohl ◽  
Clarence Merskey

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.

2005 ◽  
Vol 129 (1) ◽  
pp. 89-91 ◽  
Author(s):  
Mordechai Lorberboym ◽  
Naomi Rahimi-Levene ◽  
Helena Lipszyc ◽  
Chun K. Kim

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.


1989 ◽  
Vol 256 (4) ◽  
pp. C925-C929 ◽  
Author(s):  
I. Seferynska ◽  
J. Brookins ◽  
J. C. Rice ◽  
J. W. Fisher

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.


1965 ◽  
Vol 45 (3) ◽  
pp. 203-210 ◽  
Author(s):  
H. Doornenbal ◽  
A. H. Martin

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.


Blood ◽  
1952 ◽  
Vol 7 (4) ◽  
pp. 404-416 ◽  
Author(s):  
J. B. KAHN ◽  
J. FURTH

Abstract 1. To assess the effects of irradiation on erythrocytes in vivo, one group of rabbits was injected with radioiron-tagged erythrocytes immediately before, and a second group immediately after exposure to x-rays. A third control group received the tagged erythrocytes but no irradiation. There was a drop in red cell mass in both irradiated groups as compared with the controls, but there was no difference between the two irradiated groups, i.e., between the behavior of irradiated and nonirradiated erythrocytes in irradiated hosts. These findings indicate that there is no direct effect of irradiation in the median lethal range on erythrocytes in vivo. 2. The degree of anemia was studied as a function of irradiation dose. It requires nearly lethal doses of x-rays to cause a conspicuous anemia. In the fatally irradiated animals the drop in red cell mass and total circulating radioiron is precipitous; in those nonfatally irradiated the drop is gradual and relatively slight, even though the animals may have received the same dose. 3. Increase of specific organ activity of the liver and spleen of irradiated animals can be correlated with hemosiderin deposits and congestion. Deposition of hemosiderin is a consequence of irradiation, its degree increasing with the effectiveness of the irradiation. 4. The erythrocyte mass of rabbits obtained by two direct isotopic technics (P32 and Fe59) and one indirect technic (T-1824 dye) differ by constant ratios. The Fe59/P32 ratio is 0.89; the Fe59 values are regarded as correct. With the aid of conversion factors either technic can be used. If an indirect technic is employed and the erythrocyte mass is estimated on the basis of plasma volume measurements, it is necessary to calculate first the average body hematocrit. This is done by multiplying the large vessel hematocrit by a conversion factor, which is 0.83 in normal rabbits.


1999 ◽  
Vol 55 (2) ◽  
pp. 101-104 ◽  
Author(s):  
M. M. R. Young ◽  
L. Squassante ◽  
J. Wemer ◽  
S. P. van Marle ◽  
P. Dogterom ◽  
...  
Keyword(s):  
Red Cell ◽  

2000 ◽  
Vol 26 (1) ◽  
pp. 25-31 ◽  
Author(s):  
Ingrid Balga ◽  
Max Solenthaler ◽  
Miha Furlan
Keyword(s):  
Red Cell ◽  

Author(s):  
Javid Mansuri ◽  
Archana Paranjape

Objective: Evaluation of the anti-obesity effect of aqueous extract of Mucuna pruriens seeds on rats.Methods: Male Sprague-Dawley (SD) rats were subjected to high-fat diet (HFD) for 12 wk. L-DOPA (12.5 mg/kg, p. o.) as standard drug and aqueous extract of Mucuna pruriens (AEMP) seeds (200 mg/kg, p. o. and 400 mg/kg, p. o.) as test drugs were administered in last 4 wk along with HFD. Body weight, food intake, body mass index (BMI), serum total cholesterol (TC), triglyceride (TG) and high-density lipoprotein (HDL) levels were measured at the end of fourth, eighth and twelfth wk, while white adipose tissue (WAT) mass and brain dopamine levels were measured at the end of the twelfth wk.Results: AEMP (200 mg/kg, p. o.) and (400 mg/kg, p. o.) treated groups showed a significant decrease in food intake and weight gain without altering BMI. Moreover, TG levels were lower in treated groups as compared to the HFD group, but no significant changes were observed in TC and HDL levels. L-DOPA-treated group showed a significant decrease in body weight, food intake, BMI and WAT. Both AEMP and L-DOPA-treated groups showed an increase in brain dopamine levels as compared to disease control group (p<0.05).Conclusion: L-DOPA and AEMP showed anti-obesity activity by reducing body weight gains, food intake and WAT weights; modulating TG with increased brain dopamine level which correlates to the inhibitory action of dopamine on reward mechanism. 


1996 ◽  
Vol 270 (1) ◽  
pp. H121-H126 ◽  
Author(s):  
J. K. Shoemaker ◽  
H. J. Green ◽  
J. Coates ◽  
M. Ali ◽  
S. Grant

The purpose of this study was to investigate the time-dependent effects of long-term prolonged exercise training on vascular volumes and hematological status. Training using seven untrained males [age 21.1 +/- 1.4 (SE) yr] initially consisted of cycling at 68% of peak aerobic power (VO2peak) for 2 h/day, 4-5 days/wk, for 11 wk. Absolute training intensity was increased every 3 wk. Red cell mass (RCM), obtained using 51Cr, was unchanged (P > 0.05) with training (2,142 +/- 95, 2,168 +/- 86, 2,003 +/- 112, and 2,080 +/- 116 ml at 0, 3, 6, and 11 wk, respectively) as were serum erythropoietin levels (17.1 +/- 4.3, 13.9 +/- 3.5, and 17.0 +/- 2.0 U/l at 0, 6, and 11 wk, respectively). Plasma volume measured with 125I-labeled albumin and total blood volume (TBV) were also not significantly altered. The increase in mean cell volume that occurred with training (89.7 +/- 0.95 vs. 91.0 +/- 1.0 fl, 0 vs. 6 wk, P < 0.05) was not accompanied by changes in either mean cell hemoglobin or mean cell hemoglobin concentration. Serum ferritin was reduced 73% with training (67.4 +/- 13 to 17.9 +/- 1 microgram/l, 0 vs. 11 wk, P < 0.05). Total hemoglobin (HbTot) calculated as the product of hemoglobin concentration and TBV was unaltered (P > 0.05) at both 6 and 11 wk of training. The 15% increase in VO2peak (3.39 +/- 0.16 to 3.87 +/- 0.14 l/min, 0 vs. 11 wk, P < 0.05) with training occurred despite a failure of training to change TBV, RCM, or HbTot.


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