Intraerythrocyte and plasma osmolality during graded exercise in humans

1985 ◽  
Vol 58 (4) ◽  
pp. 1069-1072 ◽  
Author(s):  
M. J. Buono ◽  
P. E. Faucher
Keyword(s):  
Maximal Exercise ◽  
Plasma Osmolality ◽  
Hemoglobin Concentration ◽  
Exercise Bout ◽  
Cycle Ergometer ◽  
Mean Corpuscular Hemoglobin ◽  
Maximal Exercise Test ◽  
Graded Exercise ◽  
Exercise In Humans

The purpose of this study was to measure intraerythrocyte and plasma osmolality during graded exercise in humans. Eight volunteers performed a maximal exercise test on a cycle ergometer. Mean corpuscular volume, mean corpuscular hemoglobin concentration, and erythrocyte water content were not significantly (P less than 0.05) affected by the exercise bout in spite of a significant mean increase of 6.7% in plasma osmolality. Interestingly, intraerythrocyte osmolality also increased significantly during the exercise bout, paralleling the response seen in the plasma. In fact, plasma osmolality and intraerythrocyte osmolality demonstrated a significant linear relationship (r = 0.91). These data suggest that during exercise the human erythrocyte has the ability to increase its osmolality in vivo to match that of the plasma. Therefore, this mechanism allows for erythrocyte volume to remain relatively unchanged during exercise despite a significant increase in plasma osmolality.

Water and electrolyte balance in the vascular space during graded exercise in humans

1991 ◽  
Vol 70 (6) ◽  
pp. 2757-2762 ◽  
Author(s):  
H. Nose ◽  
A. Takamata ◽  
G. W. Mack ◽  
Y. Oda ◽  
T. Okuno ◽  
...  
Keyword(s):  
Exercise Intensity ◽  
Lactate Concentration ◽  
Plasma Osmolality ◽  
Cycle Ergometer ◽  
Curvilinear Relationship ◽  
Electrolyte Balance ◽  
Co2 Gas ◽  
Vascular Space ◽  
Graded Exercise ◽  
Water And Electrolyte Balance

We analyzed the changes in water content and electrolyte concentrations in the vascular space during graded exercise of short duration. Six male volunteers exercised on a cycle ergometer at 20 degrees C (relative humidity = 30%) as exercise intensity was increased stepwise until voluntary exhaustion. Blood samples were collected at exercise intensities of 29, 56, 70, and 95% of maximum aerobic power (VO2max). A curvilinear relationship between exercise intensity and Na+ concentration in plasma ([Na+]p) was observed. [Na+]p significantly increased at 70% VO2max and at 95% VO2max was approximately 8 meq/kgH2O higher than control. The change in lactate concentration in plasma ([Lac-]p) was closely correlated with the change in [Na+]p (delta[Na+]p = 0.687 delta[Lac-]p + 1.79, r = 0.99). The change in [Lac-]p was also inversely correlated with the change in HCO3- concentration in plasma (delta[HCO3-]p = -0.761 delta[Lac-]p + 0.22, r = -1.00). At an exercise intensity of 95% VO2max, 60% of the increase in plasma osmolality (Posmol) was accounted for by an increase in [Na+]p. These results suggest that lactic acid released into the vascular space from active skeletal muscles reacts with [HCO3-]p to produce CO2 gas and Lac-. The data raise the intriguing notion that increase in [Na+]p during exercise may be caused by elevated Lac-.

Erythrocyte indices during a competitive marathon

1982 ◽  
Vol 52 (1) ◽  
pp. 168-172 ◽  
Author(s):  
M. A. Kolka ◽  
L. A. Stephenson ◽  
J. E. Wilkerson
Keyword(s):  
Water Vapor Pressure ◽  
Venous Blood ◽  
Plasma Osmolality ◽  
Hemoglobin Concentration ◽  
Ambient Air ◽  
Mean Corpuscular Hemoglobin ◽  
Corpuscular Hemoglobin ◽  
Indwelling Catheter ◽  
Weight Losses ◽  
Rbc Indices

Three adult male volunteers ran a competitive marathon (42.2 km) during which there was an average ambient air (dry bulb) temperature of 19.4 degree C, with an average ambient water vapor pressure of 9.5 Toor. Prior to and at 4.8-km (3-mi) intervals throughout the race, venous blood samples were drawn from an indwelling catheter in a peripheral arm vein. In each blood sample the total erythrocyte count (EC) was made, and whole blood hemoglobin concentration, hematocrit, and plasma osmolality were determined. From these measurements, the standard red blood cell (RBC) indices of mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were calculated. The three subjects completed the race in 191, 240, and 310 min, with weight losses averaging 5.4% of prerace body weight. EC linearly decreased below the prerace control levels of 5.69 X 10(6) RBC/mm3 for the first 14.5 km of the race, so that EC was 4.7% below control levels by this point. Subsequently, EC rose back to control levels by 19.3 km, where it remained for the rest of the race. MCHC, MCH, and calculated total RBC volume did not significantly change during the race. Plasma osmolality related to plasma osmolality. These data indicate the dynamic nature of erythrocyte number and volume during long-duration submaximal exercise, and the extraordinary ability of the human body to maintain RBC indices within narrow limits when confronted with a severe stress such as the marathon.

Ventilatory Threshold and V̇O2 Plateau at Maximal Exercise in 8- to 11-Year-Old Children

1993 ◽  
Vol 5 (4) ◽  
pp. 332-338 ◽  
Author(s):  
Anthony D. Mahon ◽  
Melinda L. Marsh
Keyword(s):  
Exercise Test ◽  
Maximal Exercise ◽  
Ventilatory Threshold ◽  
Age Group ◽  
Maximal Exercise Test ◽  
Graded Exercise Test ◽  
Graded Exercise ◽  
The Mean

This study examined the occurrence of a V̇O2 plateau at maximal exercise, and whether ventilatory threshold (VT) differend between children who do and children who do not achieve a V̇O2 plateau at maximal exercise. After performing a graded exercise test on a treadmill to assess VT and V̇O2max, the children were divided into a plateau group (n = 14) and a nonplateau group (n = 12). There were no differences with respect to the V̇O2 at VT (36.7 ± 3.4 vs. 37.9 ± 5.4 ml · kg−1 · min−1) and V̇O2max (51.6 ± 5.4 vs. 54.6 ± 3.6 ml · kg−1 · min−1) in the plateau and nonpiateau groups, respectively. The mean HR, RER, and RPE at maximal exercise were also similar between groups. These results indicate that VT and V̇O2max are similar in children regardless of the occurrence of a V̇O2 plateau at maximal exercise. Furthermore, a plateau in V̇O2 during a maximal exercise test is not mandatory for assessment of V̇O2max in this age group.

scholarly journals Description on the Effects of Acute and Chronic Exercise on Different Systems of the Body

2021 ◽  
pp. 272-275
Author(s):  
Dr. K. Rama Subba Reddy ◽  
Dr. T V Bala Krishna Reddy
Keyword(s):  
Acute Exercise ◽  
Maximal Exercise ◽  
Training Programme ◽  
Cycle Ergometer ◽  
The Body ◽  
Chronic Exercise ◽  
Maximal Exercise Test ◽  
Physiological Adaptations ◽  
Exercise Programmes

The purpose of this study is to explore various changes occur in different physical and physiological systems of the body with respect to the relevant chronic exercises. Acute and Chronic exercise programmes develops physiological adaptations in different systems of the body, due to the stress places on the systems. Acute exercise refers to short duration exercise, such as a cycle ergometer or a treadmill maximal exercise test. Chronic refers to extended or long term exercise, such a physical training programme of four to six months duration.

scholarly journals The effect of acetylsalicylic acid and meloxicamon hematological parameters in rats

2015 ◽  
Vol 69 (5-6) ◽  
pp. 357-375
Author(s):  
Vitomir Cupic ◽  
Predrag Pejcic ◽  
Dragisa Trailovic ◽  
Branislav Prokic ◽  
Sasa Ivanovic ◽  
...  
Keyword(s):  
Acetylsalicylic Acid ◽  
Maximum Dose ◽  
Hematological Parameters ◽  
Hemoglobin Concentration ◽  
Male Rats ◽  
Mean Corpuscular Hemoglobin ◽  
Cyclooxygenase Inhibitor ◽  
Antiinflammatory Drugs ◽  
Hematological Indices

In this work there was investigated the effect of two nonsteroidal antiinflammatory drugs (NSAIDs), acetylsalicylic acid or aspirin (nonselective cyclooxygenase inhibitor - COX1 i COX2) and meloxicam (selective cyclooxygenase inhibitor - COX2) on certain hematological parameters in rats. The objective of the work was to determine whether (and to which extent), these drugs, after multiple peroral application, influence erythrocyte number, concentration of hemoglobin, hematological indices (mean corpuscular value - MCV; mean concentration of hemoglobin in erythrocytes - MCH; mean corpuscular hemoglobin concentration - MCHC), hematocrit, number of platelets, leukocytes, neutrophilic leukocytes, lymphocytes and monocytes. The experiment was conducted in in vivo conditions on 70 clinically healthy Wistar strain male rats, 10 to 12 weeks of age and body weight 250 to 300 g. The rats were divided into seven groups and they were daily perorally (by probe) given aspirin (ASCOPIR) at doses of 30, 40 and 80 mg/kg b.m. (I, II and III groups), or meloxicam (METACAM) at doses of 100, 125 and 250 ?g/kg b.m. (IV, V and VI groups), for seven days. The seventh group was a control one and they were given only saline. The obtained results showed that: acetylsalicylic acid in maximum dose tested (80 mg/kg b.m.) statistically significantly reduced the number of platelets (p<0,05), the number of leukocytes (p<0,05), the number of lymphocytes (p<0,05) and the number of monocytes (p<0,05), while on the other side, meloxicam in maximum dose tested (250 ?g/kg), statistically significantly reduced the mean corpuscular value (MCV), and increased the number of platelets (p<0,05), relative to the control value.

Treatment with NS3623, a novel Cl-conductance blocker, ameliorates erythrocyte dehydration in transgenic SAD mice: a possible new therapeutic approach for sickle cell disease

Blood ◽  
2001 ◽  
Vol 97 (5) ◽  
pp. 1451-1457 ◽  
Author(s):  
Poul Bennekou ◽  
Lucia de Franceschi ◽  
Ove Pedersen ◽  
Lurong Lian ◽  
Toshio Asakura ◽  
...  
Keyword(s):  
Sickle Cell Disease ◽  
Sickle Cell ◽  
Hemoglobin Concentration ◽  
Repeated Administration ◽  
K Channel ◽  
Mean Corpuscular Hemoglobin ◽  
Cell Disease ◽  
Cl Conductance

The dehydration of sickle red blood cells (RBCs) through the Ca-activated K channel depends on the parallel movement of Cl ions. To study whether Cl-conductance block might prevent dehydration of sickle RBCs, a novel Cl-conductance inhibitor (NS3623) was characterized in vitro using RBCs from healthy donors and sickle cell patients and in vivo using normal mice and a transgenic mouse model of sickle cell disease (SAD mice). In vitro, NS3623 reversibly blocked human RBC Cl-conductance (gCl) with an IC50 value of 210 nmol/L and a maximal block of 95%. In vivo, NS3623 inhibited RBC gCl after oral administration to normal mice (ED50 = 25 mg/kg). Although gCl, at a single dose of 100 mg/kg, was still 70% inhibited 5 hours after dosing, the inhibition disappeared after 24 hours. Repeated administration of 100 mg/kg twice a day for 10 days caused no adverse effects; therefore, this regimen was chosen as the highest dosing for the SAD mice. SAD mice were treated for 3 weeks with 2 daily administrations of 10, 35, and 100 mg/kg NS3623, respectively. The hematocrit increased, and the mean corpuscular hemoglobin concentration decreased in all groups with a concomitant increase in the intracellular cation content. A loss of the densest red cell population was observed in conjunction with a shift from a high proportion of sickled to well-hydrated discoid erythrocytes, with some echinocytes present at the highest dosage. These data indicate feasibility for the potential use of Cl-conductance blockers to treat human sickle cell disease.

K-Cl cotransport modulation by intracellular Mg in erythrocytes from mice bred for low and high Mg levels

2001 ◽  
Vol 281 (4) ◽  
pp. C1385-C1395 ◽  
Author(s):  
Lucia De Franceschi ◽  
Emma Villa-Moruzzi ◽  
Laura Fumagalli ◽  
Carlo Brugnara ◽  
Franco Turrini ◽  
...  
Keyword(s):  
Tyrosine Kinases ◽  
Hemoglobin Concentration ◽  
Cation Transport ◽  
Mean Corpuscular Hemoglobin ◽  
Protein Abundance ◽  
Src Family Kinase ◽  
Kinase C ◽  
Src Family Tyrosine Kinases

Mg is an important determinant of erythrocyte cation transport system(s) activity. We investigated cation transport in erythrocytes from mice bred for high (MGH) and low (MGL) Mg levels in erythrocytes and plasma. We found that K-Cl cotransport activity was higher in MGL than in MGH erythrocytes, and this could explain their higher mean corpuscular hemoglobin concentration, median density, and reduced cell K content. Although mouse KCC1 protein abundance was comparable in MGL and MGH erythrocytes, activities of Src family tyrosine kinases were higher in MGH than in MGL erythrocytes. In contrast, protein phosphatase (PP) isoform 1α (PP1α) enzymatic activity, which has been suggested to play a positive regulatory role in K-Cl cotransport, was lower in MGH than in MGL erythrocytes. Additionally, we found that the Src family kinase c-Fgr tyrosine phosphorylates PP1α in vitro. These findings suggest that in vivo downregulation of K-Cl cotransport activity by Mg is mediated by enhanced Src family kinase activity, leading to inhibition of the K-Cl cotransport stimulator PP1.

scholarly journals Azidothymidine induces severe hematological toxicity and hepatic injury in Charles Foster rats

2017 ◽  
Vol 6 (9) ◽  
pp. 2125
Author(s):  
Rajat Pandey ◽  
Ramakant Singh
Keyword(s):  
Biochemical Parameters ◽  
Hemoglobin Concentration ◽  
Total Leukocyte Count ◽  
Hematological Toxicity ◽  
Control Group ◽  
Mean Corpuscular Hemoglobin ◽  
Highly Active ◽  
Elevated Bilirubin ◽  
Histopathological Studies

Background: The present study aimed at evaluating the effects of azidothymidine (AZT) on hematologic and biochemical parameters in Charles Foster rats.Methods: Twelve adult healthy Charles Foster rats comprising of six male and six females were selected for study. Test rodents were divided into four groups containing three rodents each. Three males and three females served as control and remaining received AZT drug. Rodents were acclimatized for 10 days and drug was administered for 28 days. After the completion of drug administration, blood samples were collected and analyzed for hematologic parameters, i.e., Hemoglobin (Hb), Packed cell volume (PCV), red blood cell (RBC), Mean corpuscular hemoglobin concentration (MCHC), total leukocyte count (TLC), Mean corpuscular volume (MCV), Platelet count (Plt) using a Fully Automatic Fully Digital Hematology Cell Counter. In addition, biochemical parameters, were measured to assess the effects of AZT on rodent physiology. In-vivo histopathological studies were also performed on vital organs of rodents to understand the effects of drug at tissue level.Results: When compared with the control group, the data indicated a outstanding decrease in Hb, PCV, RBC, TLC and platelets in all test groups, whereas MCHC did not show any major reduction but MCV data suggested a slight increase. Among biochemical parameters, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP). were found to be remarkably elevated along with elevated bilirubin and reduced albumin, pointing towards a possible liver damage which was later corroborated by liver histopathological study.Conclusions: Above results indicate azidothymidine to be a myelosuppresive and hepatotoxic drug and its usage as an anti-retro viral during highly active anti-retro viral therapy (HAART) regime should be strictly monitored.

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