TY - JOUR
T1 - The effect of nitric oxide synthase inhibition with and without inhibition of prostaglandins on blood flow in different human skeletal muscles
AU - Heinonen, Ilkka
AU - Saltin, Bengt
AU - Hellsten, Ylva
AU - Kalliokoski, Kari
N1 - CURIS 2017 NEXS 123
PY - 2017/6/1
Y1 - 2017/6/1
N2 - Purpose: Animal studies suggest that the inhibition of nitric oxide synthase (NOS) affects blood flow differently in different skeletal muscles according to their muscle fibre type composition (oxidative vs glycolytic). Quadriceps femoris (QF) muscle consists of four different muscle parts: vastus intermedius (VI), rectus femoris (RF), vastus medialis (VM), and vastus lateralis (VL) of which VI is located deep within the muscle group and is generally regarded to consist mostly of oxidative muscle fibres. Methods: We studied the effect of NOS inhibition on blood flow in these four different muscles by positron emission tomography in eight young healthy men at rest and during one-leg dynamic exercise, with and without combined blockade with prostaglandins. Results: At rest blood flow in the VI (2.6 ± 1.1 ml/100 g/min) was significantly higher than in VL (1.9 ± 0.6 ml/100 g/min, p = 0.015) and RF (1.7 ± 0.6 ml/100 g/min, p = 0.0015), but comparable to VM (2.4 ± 1.1 ml/100 g/min). NOS inhibition alone or with prostaglandins reduced blood flow by almost 50% (p < 0.001), but decrements were similar in all four muscles (drug × muscle interaction, p = 0.43). During exercise blood flow was also the highest in VI (45.4 ± 5.5 ml/100 g/min) and higher compared to VL (35.0 ± 5.5 ml/100 g/min), RF (38.4 ± 7.4 ml/100 g/min), and VM (36.2 ± 6.8 ml/100 g/min). NOS inhibition alone did not reduce exercise hyperemia (p = 0.51), but combined NOS and prostaglandin inhibition reduced blood flow during exercise (p = 0.002), similarly in all muscles (drug × muscle interaction, p = 0.99). Conclusion: NOS inhibition, with or without prostaglandins inhibition, affects blood flow similarly in different human QF muscles both at rest and during low-to-moderate intensity exercise.
AB - Purpose: Animal studies suggest that the inhibition of nitric oxide synthase (NOS) affects blood flow differently in different skeletal muscles according to their muscle fibre type composition (oxidative vs glycolytic). Quadriceps femoris (QF) muscle consists of four different muscle parts: vastus intermedius (VI), rectus femoris (RF), vastus medialis (VM), and vastus lateralis (VL) of which VI is located deep within the muscle group and is generally regarded to consist mostly of oxidative muscle fibres. Methods: We studied the effect of NOS inhibition on blood flow in these four different muscles by positron emission tomography in eight young healthy men at rest and during one-leg dynamic exercise, with and without combined blockade with prostaglandins. Results: At rest blood flow in the VI (2.6 ± 1.1 ml/100 g/min) was significantly higher than in VL (1.9 ± 0.6 ml/100 g/min, p = 0.015) and RF (1.7 ± 0.6 ml/100 g/min, p = 0.0015), but comparable to VM (2.4 ± 1.1 ml/100 g/min). NOS inhibition alone or with prostaglandins reduced blood flow by almost 50% (p < 0.001), but decrements were similar in all four muscles (drug × muscle interaction, p = 0.43). During exercise blood flow was also the highest in VI (45.4 ± 5.5 ml/100 g/min) and higher compared to VL (35.0 ± 5.5 ml/100 g/min), RF (38.4 ± 7.4 ml/100 g/min), and VM (36.2 ± 6.8 ml/100 g/min). NOS inhibition alone did not reduce exercise hyperemia (p = 0.51), but combined NOS and prostaglandin inhibition reduced blood flow during exercise (p = 0.002), similarly in all muscles (drug × muscle interaction, p = 0.99). Conclusion: NOS inhibition, with or without prostaglandins inhibition, affects blood flow similarly in different human QF muscles both at rest and during low-to-moderate intensity exercise.
KW - Muscle fibres
KW - Blood flow
KW - Nitric oxide
KW - Prostanoids
KW - Exercise
KW - Humans
U2 - 10.1007/s00421-017-3604-2
DO - 10.1007/s00421-017-3604-2
M3 - Journal article
C2 - 28432421
SN - 1439-6319
VL - 117
SP - 1175
EP - 1180
JO - European Journal of Applied Physiology
JF - European Journal of Applied Physiology
IS - 6
ER -
