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Exhaustive exercise attenuates the neurovascular coupling by blunting the pressor response to visual stimulation.

Yamaguchi Y, Ikemura T, Hayashi N - Biomed Res Int (2015)

Bottom Line: Neurovascular coupling (NVC) is assessed as an increase response to visual stimulation, and is monitored by blood flow of the posterior cerebral artery (PCA).NVC was estimated as the relative change in PCAv from the mean value obtained during 20-s with the eyes closed to the peak value obtained during 40-s of visual stimulation involving looking at a reversed checkerboard.At exhaustion, PCAv was significantly decreased relative to baseline measurements, and the PCAv response to visual stimulation significantly decreased.

View Article: PubMed Central - PubMed

Affiliation: Graduate School of Human-Environment Studies, Kyushu University, Kasuga, Fukuoka 816-8580, Japan ; Graduate School of Decision Science and Technology, Tokyo Institute of Technology, Meguro, Tokyo 152-8852, Japan.

ABSTRACT
Neurovascular coupling (NVC) is assessed as an increase response to visual stimulation, and is monitored by blood flow of the posterior cerebral artery (PCA). To investigate whether exhaustive exercise modifies NVC, and more specifically, the relative contributions of vasodilatation in the downstream of PCA and the pressor response on NVC, we measured blood flow velocity in the PCA (PCAv) in 13 males using transcranial Doppler ultrasound flowmetry during a leg-cycle exercise at 75% of maximal heart rate until exhaustion. NVC was estimated as the relative change in PCAv from the mean value obtained during 20-s with the eyes closed to the peak value obtained during 40-s of visual stimulation involving looking at a reversed checkerboard. Conductance index (CI) was calculated by dividing PCAv by mean arterial pressure (MAP) to evaluate the vasodilatation. At exhaustion, PCAv was significantly decreased relative to baseline measurements, and the PCAv response to visual stimulation significantly decreased. Compared to baseline, exhaustive exercise significantly suppressed the increase in MAP to visual stimulation, while the CI response did not significantly change by the exercise. These results suggest that exhaustive exercise attenuates the magnitude of NVC by blunting the pressor response to visual stimulation.

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The relative changes in the blood flow velocity of the posterior cerebral artery (PCAv) (a), the absolute changes in the mean arterial pressure (MAP) (b), and the relative changes in the conductance index (CI) (c) from the resting baseline to the exercise and recovery periods. *P < 0.05 versus resting baseline.
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fig1: The relative changes in the blood flow velocity of the posterior cerebral artery (PCAv) (a), the absolute changes in the mean arterial pressure (MAP) (b), and the relative changes in the conductance index (CI) (c) from the resting baseline to the exercise and recovery periods. *P < 0.05 versus resting baseline.

Mentions: The duration to exhaustion was 23 ± 2 min (range 13–30 min). HR significantly increased above baseline levels throughout the exercise session (P < 0.05; Table 1). Exercise significantly increased the MAP, while it returned to baseline level after the cessation of exercise (Table 1, Figure 1(b)). PaCO2 significantly increased at 5 min after the onset of exercise, but significantly decreased at exhaustion and during the recovery period (−7 ± 2 and −11 ± 1%, resp., P < 0.05). External ear temperature significantly increased after the exhaustive exercise from baseline (35.8 ± 0.1 and 36.6 ± 0.2°C, resp., P < 0.05).


Exhaustive exercise attenuates the neurovascular coupling by blunting the pressor response to visual stimulation.

Yamaguchi Y, Ikemura T, Hayashi N - Biomed Res Int (2015)

The relative changes in the blood flow velocity of the posterior cerebral artery (PCAv) (a), the absolute changes in the mean arterial pressure (MAP) (b), and the relative changes in the conductance index (CI) (c) from the resting baseline to the exercise and recovery periods. *P < 0.05 versus resting baseline.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4383341&req=5

fig1: The relative changes in the blood flow velocity of the posterior cerebral artery (PCAv) (a), the absolute changes in the mean arterial pressure (MAP) (b), and the relative changes in the conductance index (CI) (c) from the resting baseline to the exercise and recovery periods. *P < 0.05 versus resting baseline.
Mentions: The duration to exhaustion was 23 ± 2 min (range 13–30 min). HR significantly increased above baseline levels throughout the exercise session (P < 0.05; Table 1). Exercise significantly increased the MAP, while it returned to baseline level after the cessation of exercise (Table 1, Figure 1(b)). PaCO2 significantly increased at 5 min after the onset of exercise, but significantly decreased at exhaustion and during the recovery period (−7 ± 2 and −11 ± 1%, resp., P < 0.05). External ear temperature significantly increased after the exhaustive exercise from baseline (35.8 ± 0.1 and 36.6 ± 0.2°C, resp., P < 0.05).

Bottom Line: Neurovascular coupling (NVC) is assessed as an increase response to visual stimulation, and is monitored by blood flow of the posterior cerebral artery (PCA).NVC was estimated as the relative change in PCAv from the mean value obtained during 20-s with the eyes closed to the peak value obtained during 40-s of visual stimulation involving looking at a reversed checkerboard.At exhaustion, PCAv was significantly decreased relative to baseline measurements, and the PCAv response to visual stimulation significantly decreased.

View Article: PubMed Central - PubMed

Affiliation: Graduate School of Human-Environment Studies, Kyushu University, Kasuga, Fukuoka 816-8580, Japan ; Graduate School of Decision Science and Technology, Tokyo Institute of Technology, Meguro, Tokyo 152-8852, Japan.

ABSTRACT
Neurovascular coupling (NVC) is assessed as an increase response to visual stimulation, and is monitored by blood flow of the posterior cerebral artery (PCA). To investigate whether exhaustive exercise modifies NVC, and more specifically, the relative contributions of vasodilatation in the downstream of PCA and the pressor response on NVC, we measured blood flow velocity in the PCA (PCAv) in 13 males using transcranial Doppler ultrasound flowmetry during a leg-cycle exercise at 75% of maximal heart rate until exhaustion. NVC was estimated as the relative change in PCAv from the mean value obtained during 20-s with the eyes closed to the peak value obtained during 40-s of visual stimulation involving looking at a reversed checkerboard. Conductance index (CI) was calculated by dividing PCAv by mean arterial pressure (MAP) to evaluate the vasodilatation. At exhaustion, PCAv was significantly decreased relative to baseline measurements, and the PCAv response to visual stimulation significantly decreased. Compared to baseline, exhaustive exercise significantly suppressed the increase in MAP to visual stimulation, while the CI response did not significantly change by the exercise. These results suggest that exhaustive exercise attenuates the magnitude of NVC by blunting the pressor response to visual stimulation.

Show MeSH
Related in: MedlinePlus