Neuropeptide Y release from human heart is enhanced during prolonged exercise in hypoxia

1994 ◽  
Vol 76 (3) ◽  
pp. 1346-1349 ◽  
Author(s):  
L. Kaijser ◽  
J. Pernow ◽  
B. Berglund ◽  
J. Grubbstrom ◽  
J. M. Lundberg
Keyword(s):  
Neuropeptide Y ◽  
Coronary Sinus ◽  
Cycle Ergometer ◽  
Air Breathing ◽  
Ergometer Exercise ◽  
The Difference ◽  
Exercise Induced ◽  
Arterial O2 Saturation ◽  
Net Release ◽  
Coronary Sinus Blood

To evaluate the effect of hypoxemia on cardiac release of neuropeptide Y-like immunoreactivity (NPY-LI) and norepinephrine (NE), arterial and coronary sinus blood was sampled and coronary sinus blood flow was measured by thermodilution in nine healthy volunteers at rest and during supine cycle ergometer exercise while they breathed air and 12% O2, which reduced arterial O2 saturation to approximately 68%. Five subjects started to exercise for 30 min breathing air and continued for 30 min breathing 12% O2; four subjects breathed 12% O2 and air in the reverse order. The load was adjusted to give the same heart rate during O2 and air breathing. No significant cardiac net release of NPY-LI or NE was seen at rest. Exercise induced release of NPY-LI and NE. The net release of NPY-LI was 0.7 +/- 0.4 pmol/min during air breathing (average 12 and 30 min) and 2.8 +/- 0.6 pmol/min during 12% O2 breathing. The difference was not influenced by the order of the breathing periods. The NE coronary sinus-arterial difference was not significantly different between 12% O2 and air breathing, whereas the net release was significantly larger during 12% O2 breathing (0.6 +/- 0.1 vs. 0.4 +/- 0.1 nmol/min). Thus, NPY is released with NE from the heart during exercise. Arterial hypoxemia seems to be an additional stimulus of preferential NPY release.

Leg raise can detect exercise-induced pulmonary arterial wedge pressure elevation

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
C Nakata ◽  
A Goda ◽  
K Takeuchi ◽  
H Kikuchi ◽  
T Inami ◽  
...  
Keyword(s):  
Diastolic Dysfunction ◽  
Cycle Ergometer ◽  
Left Ventricular Diastolic Dysfunction ◽  
Left Ventricular ◽  
Hemodynamic Assessment ◽  
Ergometer Exercise ◽  
Ventricular Diastolic Dysfunction ◽  
Pulmonary Arterial ◽  
Exercise Induced ◽  
Wedge Pressure

Abstract Background Exercise-induced elevation of pulmonary arterial wedge pressure (PAWP) may show preclinical or exercise-induced left ventricular diastolic dysfunction. Invasive hemodynamic assessment during provocative maneuvers, like exercise and volume challenge, in these patients allows greater sensitivity to diagnose or exclude HFpEF. The aim of this study was to examine how the leg raise, which is a simple way to increase preload, can detect exercise-induced PAWP elevation. Methods Four hundred seventy-nine patients (60±14y.o, mean pulmonary arterial pressure (PAP) 19mmHg, PAWP 8mmHg, CTEPH /IPAH/CTD-PH/SOB unknown reason: 357/56/38/28pts) with near-normal PAP and normal PAWP at rest underwent symptom-limited exercise test using supine cycle ergometer with right heart catheter. Exercise-induced elevation in PAWP of over 20mmHg was defined as exercise-induced elevation group. Results ΔPAWP (after leg raise - rest) in the exercise-induced elevation group was significantly higher (6.0±4.1 vs. 2.7±3.9mmHg, p<0.001, in the older (age≥60y.o) group (n=276); 3.4±3.5 vs. 1.9±3.4mmHg, p<0.001, in the younger (age<60y.o) group (n=203)) than that in the non-elevation group after legs raise for cycle ergometer exercise. The area under the ROC curve for ΔPAWP was 0.72 (95% CI: 0.65–0.78) in the older and 0.64 (95% CI: 0.53–0.75) in the younger. In the older, the cut-off value for detect exercise-induced PAWP elevation of ΔPAWP was 4mmHg, with 72% sensitivity and 58% specificity. On the other hand, in the younger, the cut-off value was 3mmHg, with 69% sensitivity and 59% specificity. Conclusion Leg raise can easily detect occult left ventricular diastolic dysfunction. Funding Acknowledgement Type of funding source: None

Transcapillary escape rate of albumin in humans during exercise-induced hypervolemia

1997 ◽  
Vol 83 (2) ◽  
pp. 407-413 ◽  
Author(s):  
Andrew Haskell ◽  
Ethan R. Nadel ◽  
Nina S. Stachenfeld ◽  
Kei Nagashima ◽  
Gary W. Mack
Keyword(s):  
Osmotic Pressure ◽  
Colloid Osmotic Pressure ◽  
Cycle Ergometer ◽  
Escape Rate ◽  
Albumin Concentration ◽  
Vascular Space ◽  
Transcapillary Escape Rate ◽  
Ergometer Exercise ◽  
Leg Muscle ◽  
Exercise Induced

Haskell, Andrew, Ethan R. Nadel, Nina S. Stachenfeld, Kei Nagashima, and Gary W. Mack. Transcapillary escape rate of albumin in humans during exercise-induced hypervolemia. J. Appl. Physiol. 83(2): 407–413, 1997.—To test the hypotheses that plasma volume (PV) expansion 24 h after intense exercise is associated with reduced transcapillary escape rate of albumin (TERalb) and that local changes in transcapillary forces in the previously active tissues favor retention of protein in the vascular space, we measured PV, TERalb, plasma colloid osmotic pressure (COPp), interstitial fluid hydrostatic pressure (Pi), and colloid osmotic pressure in leg muscle and skin and capillary filtration coefficient (CFC) in the arm and leg in seven men and women before and 24 h after intense upright cycle ergometer exercise. Exercise expanded PV by 6.4% at 24 h (43.9 ± 0.8 to 46.8 ± 1.2 ml/kg, P< 0.05) and decreased total protein concentration (6.5 ± 0.1 to 6.3 ± 0.1 g/dl, P < 0.05) and COPp (26.1 ± 0.8 to 24.3 ± 0.9 mmHg, P < 0.05), although plasma albumin concentration was unchanged. TERalb tended to decline (8.4 ± 0.5 to 6.5 ± 0.7%/h, P = 0.11) and was correlated with the increase in PV ( r = −0.69, P < 0.05). CFC increased in the leg (3.2 ± 0.2 to 4.3 ± 0.5 μl ⋅ 100 g−1 ⋅ min−1 ⋅ mmHg−1, P < 0.05), and Pi showed a trend to increase in the leg muscle (2.8 ± 0.7 to 3.8 ± 0.3 mmHg, P = 0.08). These data demonstrate that TERalb is associated with PV regulation and that local transcapillary forces in the leg muscle may favor retention of albumin in the vascular space after exercise.

scholarly journals Oxygen cost and oxygen uptake dynamics and recovery with 1 min of exercise in children and adults

1991 ◽  
Vol 71 (3) ◽  
pp. 993-998 ◽  
Author(s):  
S. Zanconato ◽  
D. M. Cooper ◽  
Y. Armon
Keyword(s):  
Time Course ◽  
Significant Degree ◽  
Cycle Ergometer ◽  
Work Intensity ◽  
O2 Uptake ◽  
Ergometer Exercise ◽  
Adults And Children ◽  
The Difference ◽  
Recovery Dynamics ◽  
Best Fit

To test the hypothesis that O2 uptake (VO2) dynamics are different in adults and children, we examined the response to and recovery from short bursts of exercise in 10 children (7–11 yr) and 13 adults (26–42 yr). Each subject performed 1 min of cycle ergometer exercise at 50% of the anaerobic threshold (AT), 80% AT, and 50% of the difference between the AT and the maximal O2 uptake (VO2max) and 100 and 125% VO2max. Gas exchange was measured breath by breath. The cumulative O2 cost [the integral of VO2 (over baseline) through exercise and 10 min of recovery (ml O2/J)] was independent of work intensity in both children and adults. In above-AT exercise, O2 cost was significantly higher in children [0.25 +/- 0.05 (SD) ml/J] than in adults (0.18 +/- 0.02 ml/J, P less than 0.01). Recovery dynamics of VO2 in above-AT exercise [measured as the time constant (tau VO2) of the best-fit single exponential] were independent of work intensity in children and adults. Recovery tau VO2 was the same in both groups except at 125% VO2max, where tau VO2 was significantly smaller in children (35.5 +/- 5.9 s) than in adults (46.3 +/- 4 s, P less than 0.001). VO2 responses (i.e., time course, kinetics) to short bursts of exercise are, surprisingly, largely independent of work rate (power output) in both adults and children. In children, certain features of the VO2 response to high-intensity exercise are, to a small but significant degree, different from those in adults, indicating an underlying process of physiological maturation.

Exercise endurance and arterial desaturation in normobaric hypoxia with increased chemosensitivity

1991 ◽  
Vol 70 (4) ◽  
pp. 1770-1774 ◽  
Author(s):  
G. G. Giesbrecht ◽  
A. Puddy ◽  
M. Ahmed ◽  
M. Younes ◽  
N. R. Anthonisen
Keyword(s):  
Cycle Ergometer ◽  
Normobaric Hypoxia ◽  
Endurance Time ◽  
Almitrine Bismesylate ◽  
Air Breathing ◽  
Warm Up ◽  
Exercise Endurance ◽  
Arterial O2 Saturation ◽  
Hypoxic Exercise ◽  
Rest And Exercise

We studied whether exercise endurance under normobaric hypoxia can be enhanced by increasing hypoxic ventilatory sensitivity with almitrine bismesylate (ALM). On both ALM and placebo (PL) days, resting subjects breathed a hypoxic gas mixture (an inspired O2 fraction of 10.4-13.2%), which lowered resting arterial O2 saturation (SaO2) to 80%. After 15 min of rest there was a 3-min warm-up period of exercise at 50 W (light) on a cycle ergometer, followed by a step increase in load to 60% of the previously determined maximum power output with room-air breathing (moderate), which was maintained until exhaustion. With PL, SaO2 decreased rapidly with the onset of exercise and continued to fall slowly during moderate exercise, averaging 71.0 +/- 1.8% (SE) at exhaustion. With ALM, saturation did not differ from PL during air breathing but significantly exceeded SaO2 with PL, by 3.4% during resting hypoxia, by 4.0% at the start of exercise, and by 5.9% at exhaustion. Ventilation was not affected by ALM during air breathing and was slightly, although not significantly, increased during hypoxic rest and exercise. ALM was associated with an increased heart rate during room air breathing but not during hypoxia. Endurance time was 20.6 +/- 1.6 min with ALM and 21.3 +/- 0.9 min with PL. During hypoxic exercise, the potential benefit of greater saturation with ALM is apparently offset by other unidentified factors.

Exercise-induced changes in blood zinc and related proteins in humans

1985 ◽  
Vol 58 (5) ◽  
pp. 1453-1458 ◽  
Author(s):  
H. Ohno ◽  
K. Yamashita ◽  
R. Doi ◽  
K. Yamamura ◽  
T. Kondo ◽  
...  
Keyword(s):  
Carbonic Anhydrase ◽  
Zinc Concentration ◽  
Plasma Concentrations ◽  
Cycle Ergometer ◽  
Male Students ◽  
Ergometer Exercise ◽  
Exercise Induced ◽  
Induced Changes ◽  
Related Proteins ◽  
Blood Zinc

Effects of cycle ergometer exercise (approximately 75% maximum ventilatory O2 consumption for 30 min) on the concentrations of zinc and related proteins in erythrocytes and/or plasma were studied on 11 sedentary male students. Lower concentrations of total zinc and of zinc derived from carbonic anhydrase I type (CA-I) in erythrocytes were observed immediately after exercise, but they disappeared after 30 min of rest. The change in total zinc concentration in erythrocytes correlated well with that in CA-I concentration immediately after exercise, as well as after rest. The concentration of carbonic anhydrase II type (CA-II)-derived zinc did not vary substantially at any time. On the other hand, there were significant increases in the plasma concentrations of total zinc and of alpha 2-macroglobulin (alpha 2-MG)-bound zinc immediately after exercise, whereas no such effect was noted in albumin-bound zinc. A positive correlation was found between total zinc and alpha 2-MG concentrations in plasma immediately after exercise. In addition, the change in the activity of alkaline phosphatase, a zinc metalloenzyme, correlated well with that in the total zinc concentration in plasma. These results suggest that a brief physical exercise induces the movement of zinc into plasma.

Exercise increases the level of plasma orexin A in humans

2016 ◽  
Vol 27 (6) ◽  
Author(s):  
Giovanni Messina ◽  
Giovanni Di Bernardo ◽  
Andrea Viggiano ◽  
Vincenzo De Luca ◽  
Vincenzo Monda ◽  
...  
Keyword(s):  
Physical Activity ◽  
Rectal Temperature ◽  
Exercise Bout ◽  
Cycle Ergometer ◽  
The Other ◽  
Orexin A ◽  
Blood Samples ◽  
Ergometer Exercise ◽  
Skin Response ◽  
Exercise Induced

AbstractBackground:The purpose of this research was to study the effects of exercise on the concentration of plasma orexin A, a peptide regulating several physiological functions.Methods:Blood samples were collected from participants (men, n=10; age: 24.4±2.93 years) 15, 0 min before the start of exercise, and 30, 45, 60 min after a cycle ergometer exercise at 75 W for 15 min. Also heart rate (HR), galvanic skin response (GSR), and rectal temperature were monitored.Results:The exercise induced a significant increase (p<0.01) in plasmatic orexin A with a peak at 30 min after the exercise bout, in association with an increase of the other three monitored variables: HR (p<0.01), GSR (p<0.05), and rectal temperature (p<0.01).Conclusions:Our findings indicate that plasmatic orexin A is involved in the reaction to physical activity.

scholarly journals Post-exercise urinary alpha-1 acid glycoprotein is not dependent on hypoxia

2021 ◽  
Author(s):  
Kelsey Elizabeth Joyce ◽  
George M. Balanos ◽  
Christopher Bradley ◽  
Amy Fountain ◽  
Arthur Randell Bradwell ◽  
...  
Keyword(s):  
Maximal Exercise ◽  
Cycle Ergometer ◽  
Performance Outcomes ◽  
Peak Power Output ◽  
Post Exercise ◽  
Acid Glycoprotein ◽  
The Difference ◽  
Exercise Induced ◽  
Physiologic Responses ◽  
Urine Specimens

Introduction: Proteinuria is a transient physiologic phenomenon that occurs with a range of physical activities and during ascent to altitude. Exercise intensity appears to dictate the magnitude of post-exercise proteinuria; however, evidence also indicates possible contributions from exercise-induced hypoxemia or reoxygenation. Utilizing an environmental hypoxic chamber, this crossover designed study aimed to evaluate urinary alpha-1 acid glycoprotein (α1-AGP) excretion pre/post exercise performed in hypoxia and normoxia. Methods: Sixteen individuals underwent experimental sessions in normoxia (NOR, 20.9% O2) and hypoxia (HYP, 12.0% O2). Sessions began with a 2-hour priming period before completing a graded maximal exercise test (GXT) on a cycle ergometer, which was followed by continuation of exposure for an additional 2 hours. Physiologic responses (i.e., blood pressure, heart rate, and peripheral oxygenation), Lake Louise Scores, and urine specimens (analyzed for albumin and α1-AGP) were collected pre- and post-exercise (after 30, 60, and 120 minutes). Results: Peak power output was significantly reduced in HYP (193 ± 45 W) compared to NOR (249 ± 59 W, p < 0.01). Post-exercise urinary α1-AGP was greater in NOR (20.04 ± 14.84 μg•min-1) compared to HYP (15.08 ± 13.46 μg•min-1), albeit the difference was not significant (p > 0.05). Changes in urinary α1-AGP from pre- to post-30 minutes were not related to physiologic responses or performance outcomes observed during GXT in NOR or HYP. Conclusion: Despite profound systemic hypoxemia with maximal exercise in hypoxia, post-exercise α1-AGP excretion was not elevated above levels observed following normoxic exercise.

Diagnostic usefulness of passive leg raising test for detection of heart failure with preserved ejection fraction compared to cycle ergometer exercise (invasive hemodynamic study)

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
S.J Hwang ◽  
M.G Kang ◽  
K.H Kim ◽  
H.W Park ◽  
J.S Koh ◽  
...  
Keyword(s):  
Ejection Fraction ◽  
Exercise Test ◽  
Diastolic Pressure ◽  
Cycle Ergometer ◽  
Left Ventricular ◽  
Passive Leg Raising ◽  
Preserved Ejection Fraction ◽  
Cycle Ergometer Exercise ◽  
Ergometer Exercise ◽  
Exercise Induced

Abstract Background Invasive diastolic stress test using cycle ergometer is gold standard for diagnosis of heart failure with preserved ejection fraction (HFpEF) by demonstrating elevation of left ventricular end diastolic pressure (LVEDP) during exercise. It is well known that passive leg raising increases preload and augments LVEDP in HFpEF patients. However correlation between passive leg raising induced increase of LVEDP and cycle ergometer exercise induced increase of LVEDP is not well established. Therefore we investigated whether passive leg raising test could substitute cycle exercise test for diagnosis of HFpEF. Method Forty-five patients with unexplained dyspnea and ejection fraction &gt;50% underwent invasive exercise test. After measuring baseline LVEDP in supine position using pigtail catheter through radial artery approach, LVEDP during passive leg raising was evaluated. Then exercise LVEDP was measured after 3 minutes of 20 watt supine cycle ergometer exercise. Patients with normal resting LVEDP &lt;16mmHg were enrolled. Patients with cycle ergometer exercise LVEDP &gt;26mmHg were classified as HFpEF and exercise LVEDP &lt;26mmHg were defined as noncardiac dyspnea. Results Among 45 patients with unexplained dyspnea with preserved EF, 30 patients with ergometer exercise LVEDP &gt;26mmHg were grouped as HFpEF and 15 patients with exercise LVEDP &lt;26mmHg grouped as noncardiac dyspnea (NCD). Resting LVEDP was higher in HFpEF than NCD (14±2mmHg vs 11±3mmHg, P=0.01) but there was substantial overlap (figure 1) showing poor differentiation power of resting LVEDP. Passive leg raising increased LVEDP in both HFpEF and NCD but this was more marked in HFpEF group than in NCD group with minimal overlap (24±4mmHg vs 17±2mmHg, P&lt;0.001) (figure 2). Passive leg raising LVEDP was well correlated with cycle ergometer exercise LVEDP (R2=0.60, P&lt;0.01). The best cutoff value for passive leg raising LVEDP to detect HFpEF was 20mmHg (sensitivity, 0.87; specificity, 1.00), giving an area under the curve of 0.93 (95% confidence interval, 0.80 to 0.99). Positive predictive value of passive leg raising LVEDP &gt;20mmHg for diagnosis of HFpEF was 96% and negative predictive value was 77%. Conclusion Passive leg raising induced augmentation of left ventricular end diastolic pressure (LVEDP) was well correlated with cycle exercise induced elevation of LVEDP in HFpEF patients. Passive leg raising test may be used for detecting HFpEF with good accuracy in substitution for cycle ergometer exercise test. Funding Acknowledgement Type of funding source: None

Effects of incomplete pulmonary gas exchange on VO2 max

1989 ◽  
Vol 66 (6) ◽  
pp. 2491-2495 ◽  
Author(s):  
S. K. Powers ◽  
J. Lawler ◽  
J. A. Dempsey ◽  
S. Dodd ◽  
G. Landry
Keyword(s):  
Gas Exchange ◽  
Sea Level ◽  
Maximal Exercise ◽  
Cycle Ergometer ◽  
Pulmonary Gas Exchange ◽  
Endurance Athletes ◽  
Healthy Male ◽  
Exercise Tests ◽  
Ergometer Exercise ◽  
Exercise Induced

Recent evidence suggests that heavy exercise may lower the percentage of O2 bound to hemoglobin (%SaO2) by greater than or equal to 5% below resting values in some highly trained endurance athletes. We tested the hypothesis that pulmonary gas exchange limitations may restrict VO2max in highly trained athletes who exhibit exercise-induced hypoxemia. Twenty healthy male volunteers were divided into two groups according to their physical fitness status and the demonstration of exercise-induced reductions in %SaO2 less than or equal to 92%: 1) trained (T), mean VO2max = 56.5 ml.kg-1.min-1 (n = 13) and 2) highly trained (HT) with maximal exercise %SaO2 less than or equal to 92%, mean VO2max = 70.1 ml.kg-1.min-1 (n = 7). Subjects performed two incremental cycle ergometer exercise tests to determine VO2max at sea level under normoxic (21% O2) and mild hyperoxic conditions (26% O2). Mean %SaO2 during maximal exercise was significantly higher (P less than 0.05) during hyperoxia compared with normoxia in both the T group (94.1 vs. 96.1%) and the HT group (90.6 vs. 95.9%). Mean VO2max was significantly elevated (P less than 0.05) during hyperoxia compared with normoxia in the HT group (74.7 vs. 70.1 ml.kg-1.min-1). In contrast, in the T group, no mean difference (P less than 0.05) existed between treatments in VO2max (56.5 vs. 57.1 ml.kg-1.min-1). These data suggest that pulmonary gas exchange may contribute significantly to the limitation of VO2max in highly trained athletes who exhibit exercise-induced reductions in %SaO2 at sea level.(ABSTRACT TRUNCATED AT 250 WORDS)

Ten days of exercise training reduces glucose production and utilization during moderate-intensity exercise

1994 ◽  
Vol 266 (1) ◽  
pp. E136-E143 ◽  
Author(s):  
L. A. Mendenhall ◽  
S. C. Swanson ◽  
D. L. Habash ◽  
A. R. Coggan
Keyword(s):  
Endurance Training ◽  
Time Course ◽  
Plasma Concentrations ◽  
Glucose Production ◽  
Peak Oxygen Uptake ◽  
Cycle Ergometer ◽  
Moderate Intensity ◽  
Moderate Intensity Exercise ◽  
Ergometer Exercise ◽  
Exercise Induced

We have previously shown that 12 wk of endurance training reduces the rate of glucose appearance (Ra) during submaximal exercise (Coggan, A. R., W. M. Kohrt, R. J. Spina, D. M. Bier, and J. O. Holloszy. J. Appl. Physiol. 68: 990-996, 1990). The purpose of the present study was to examine the time course of and relationship between training-induced alterations in glucose kinetics and endocrine responses during prolonged exercise. Accordingly, seven men were studied during 2 h of cycle ergometer exercise at approximately 60% of pretraining peak oxygen uptake on three occasions: before, after 10 days, and after 12 wk of endurance training. Ra was determined using a primed, continuous infusion of [6,6-2H]glucose. Ten days of training reduced mean Ra during exercise from 36.9 +/- 3.3 (SE) to 28.5 +/- 3.4 mumol.min-1.kg-1 (P < 0.001). Exercise-induced changes in insulin, C-peptide, glucagon, norepinephrine, and epinephrine were also significantly blunted. After 12 wk of training, Ra during exercise was further reduced to 21.5 +/- 3.1 mumol.min-1.kg-1 (P < 0.001 vs. 10 days), but hormone concentrations were not significantly different from 10-day values. The lower glucose Ra during exercise after short-term (10 days) training is accompanied by, and may be due to, altered plasma concentrations of the major glucoregulatory hormones. However, other adaptations must be responsible for the further reduction in Ra with more prolonged training.

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