Blood flow and oxygenation in peritendinous tissue and calf muscle during dynamic exercise in humans

Citation
R. Boushel et al., Blood flow and oxygenation in peritendinous tissue and calf muscle during dynamic exercise in humans, J PHYSL LON, 524(1), 2000, pp. 305-313
Citations number
40
Categorie Soggetti
Physiology
Journal title
JOURNAL OF PHYSIOLOGY-LONDON
ISSN journal
00223751 → ACNP
Volume
524
Issue
1
Year of publication
2000
Pages
305 - 313
Database
ISI
SICI code
0022-3751(20000401)524:1<305:BFAOIP>2.0.ZU;2-K
Abstract
1. Circulation around tendons may act as a shunt for muscle during exercise . The perfusion and oxygenation of Achilles' peritendinous tissue was measu red in parallel with that of calf muscle during exercise to determine (1) w hether Mood flow is restricted in peritendinous tissue during exercise, and (2) whether blood flow is coupled to oxidative metabolism. 2. Seven individuals performed dynamic plantar flexion from 1 to 9 W. Radia l artery and popliteal venous blood were sampled for O-2 peritendinous bloo d flow was determined by Xe-133-washout, calf blood flow by plethysmography , cardiac output by dye dilution, arterial pressure by an arterial catheter -transducer, and muscle and peritendinous O-2 saturation by spatially resol ved spectroscopy (SRS). 3. Calf blood flow rose 20-fold with exercise, reaching 44 +/- 7 ml(100 g)( -1) min(-1) (mean +/- S.E.M.) at 9 W, while Achilles' peritendinous flow in creased (7-fold) to 14 +/- 4 ml (100 g)(-1) min(-1) which was 18% of the ma ximal flow established during reactive hyperaemia. SRS-O-2 saturation fell both in muscle (from 66 +/- 2% at rest to 57 +/- 3%, P < 0.05) and in perit endinous regions (58 +/- 4 to 52 +/- 4%, P < 0.05) during exercise along wi th a rise in leg vascular conductance and microvascular haemoglobin volume, despite elevated systemic vascular resistance. 4. The parallel rise in calf muscle and peritendinous blood flow and fall i n O-2 saturation during exercise indicate that blood flow is coupled to oxi dative metabolism in both tissue regions. Increased leg vascular conductanc e accompanied by elevated microvascular haemoglobin volume reflect vasodila tation in both muscle and peritendinous regions. However, peak exercise per itendinous Mood flow reaches only similar to 20 % of its maximal blood flow capacity.