TY - JOUR

T1 - The effect of purinergic P2 receptor blockade on skeletal muscle exercise hyperemia in miniature swine

AU - Mortensen, Stefan Peter

AU - McAllister, R M

AU - Yang, H T

AU - Hellsten, Ylva

AU - Laughlin, M H

N1 - CURIS 2014 NEXS 230

PY - 2014

Y1 - 2014

N2 - PURPOSE: ATP could play an important role in skeletal muscle blood flow regulation by inducing vasodilation via purinergic P2 receptors. This study investigated the role of P2 receptors in exercise hyperemia in miniature swine.METHODS: We measured regional blood flow with radiolabeled-microsphere technique and systemic hemodynamics before and after arterial infusion of the P2 receptor antagonist reactive blue 2 during treadmill exercise (5.2 km/h, ~60 % VO2max) and arterial ATP infusion in female Yucatan miniature swine (~29 kg).RESULTS: Mean blood flow during exercise from the 16 sampled skeletal muscle tissues was 138 ± 18 mL/min/100 g (mean ± SEM), and it was reduced in 11 (~25 %) of the 16 sampled skeletal muscles after RB2 was infused. RB2 also lowered diaphragm blood flow and kidney blood flow, whereas lung tissue blood flow was increased (all P < 0.05). Infusion of RB2 increased arterial lactate concentration during exercise from 1.6 ± 0.5 to 3.4 ± 0.6 mmol/L and heart rate from 216 ± 12 to 230 ± 9 beats/min, whereas blood pressure was unaltered. Arterial ATP infusion caused a ~twofold increase in blood flow in 15 of the 16 sampled muscle tissues and this effect was abolished after RB2 infusion.CONCLUSIONS: These results indicate that P2 receptors play a role in regulating skeletal muscle blood flow during exercise in miniature swine.

AB - PURPOSE: ATP could play an important role in skeletal muscle blood flow regulation by inducing vasodilation via purinergic P2 receptors. This study investigated the role of P2 receptors in exercise hyperemia in miniature swine.METHODS: We measured regional blood flow with radiolabeled-microsphere technique and systemic hemodynamics before and after arterial infusion of the P2 receptor antagonist reactive blue 2 during treadmill exercise (5.2 km/h, ~60 % VO2max) and arterial ATP infusion in female Yucatan miniature swine (~29 kg).RESULTS: Mean blood flow during exercise from the 16 sampled skeletal muscle tissues was 138 ± 18 mL/min/100 g (mean ± SEM), and it was reduced in 11 (~25 %) of the 16 sampled skeletal muscles after RB2 was infused. RB2 also lowered diaphragm blood flow and kidney blood flow, whereas lung tissue blood flow was increased (all P < 0.05). Infusion of RB2 increased arterial lactate concentration during exercise from 1.6 ± 0.5 to 3.4 ± 0.6 mmol/L and heart rate from 216 ± 12 to 230 ± 9 beats/min, whereas blood pressure was unaltered. Arterial ATP infusion caused a ~twofold increase in blood flow in 15 of the 16 sampled muscle tissues and this effect was abolished after RB2 infusion.CONCLUSIONS: These results indicate that P2 receptors play a role in regulating skeletal muscle blood flow during exercise in miniature swine.

U2 - 10.1007/s00421-014-2932-8

DO - 10.1007/s00421-014-2932-8

M3 - Journal article

C2 - 24962002

VL - 114

SP - 2147

EP - 2155

JO - Journal of Applied Physiology

JF - Journal of Applied Physiology

SN - 8750-7587

IS - 10

ER -