-
[show abstract]
[hide abstract]
ABSTRACT: Alternative measures of muscle size, strength, and power to those used in previous studies could help resolve the controversy surrounding associations between polymorphisms of the angiotensin-I converting enzyme (ACE) and α-actinin-3 (ACTN3) genes and skeletal muscle phenotypes, and the responses to resistance training (RT). To this end, we measured quadriceps femoris muscle volume (V(m) ), physiological cross-sectional area (PCSA), maximum isometric force (F(t) ), specific force (F(t) per unit PCSA), maximum isoinertial strength (1-RM), and maximum power (W(max) ; n = 40) before and after 9-week knee extension RT in 51 previously untrained young men, who were genotyped for the ACE I/D and ACTN3 R577X polymorphisms. ACTN3 R-allele carriers had greater V(m) , 1-RM, and W(max) than XX homozygotes at baseline (all P < 0.05), but responses to RT were independent of ACTN3 genotype (all P > 0.05). Muscle phenotypes were independent of ACE genotype before (all P > 0.05) and after RT (all P > 0.01). However, people with the "optimal" ACE+ACTN3 genotype combination had greater baseline 1-RM and W(max) compared to those with the "suboptimal" profile (both P < 0.0125). We show for the first time that the ACTN3 R577X polymorphism is associated with human V(m) and (independently and in combination with the ACE I/D polymorphism) influences 1-RM and W(max) .
Scandinavian Journal of Medicine and Science in Sports 02/2013; · 2.87 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: It has been suggested that the number of myonuclei in a muscle fibre changes in proportion to the change in fibre size, resulting in a constant myonuclear domain size, defined as the cytoplasmic volume per myonucleus. The myonuclear domain size varies, however, between fibre types and is inversely related with the oxidative capacity of a fibre. Overall, the observations of an increase in myonuclear domain size during both maturational growth and overload-induced hypertrophy, and the decrease in myonuclear domain size during disuse- and ageing-associated muscle atrophy suggest that the concept of a constant myonuclear domain size needs to be treated cautiously. It also suggests that only when the myonuclear domain size exceeds a certain threshold during growth or overload-induced hypertrophy acquisition of new myonuclei is required for further fibre hypertrophy.
Journal of musculoskeletal & neuronal interactions 12/2011; 11(4):286-97. · 2.00 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Sequence variations in the gene encoding the hypoxia-inducible factor-1alpha, HIF1A, have been associated with physiologic function and could be associated with exercise responses. In the HIF1A P582S gene polymorphism (C1772T; rs 11549465 C/T), a single nucleotide transition from C → T alters the codon sequence from the usual amino acid; proline (C-allele), to serine (T-allele). This polymorphism was examined for association with endurance training responses in 58 untrained young women who completed a 6-week laboratory-based endurance training programme. Participant groups were defined as CC homozygotes versus carriers of a T-allele (CC vs. CT genotypes). Adaptations were examined at the systemic-level, by measuring [Formula: see text] and the molecular-level by measuring enzymes determined from vastus lateralis (n = 20): 3-hydroacyl-CoA-dehydrogenase (HAD), which regulates mitochondrial fatty acid oxidation; cytochrome C oxidase (COX-1), a marker of mitochondrial density; and phosphofructokinase (PFK), a marker of glycolytic capacity. CT genotypes showed 45% higher training-induced gains in [Formula: see text] compared with CC genotypes (P < 0.05). At the molecular level, CT increased the ratios PFK/HAD and PFK/COX-1 (47 and 3%, respectively), while in the CC genotypes these ratios were decreased (-26 and -54%, respectively). In conclusion, the T-allele of HIF1A P582S was associated with greater gains in [Formula: see text] following endurance training in young women. In a sub-group we also provide preliminary evidence of differential muscle metabolic adaptations between genotypes.
Arbeitsphysiologie 02/2011; 111(9):2339-47. · 2.15 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Vitamin D deficiency is associated with muscle weakness. It is unknown, however, how supra-physiological levels of vitamin D affect skeletal muscle. To investigate the effects of increased serum vitamin D (1,25 (OH)₂D₃ or 1,25D) levels on the contractile properties of the medial gastrocnemius muscle, adult and old female Fischer₃₄₄ x Brown Norway F1 rats were orally treated with vehicle or the vitamin D analogue alfacalcidol for 1 or 6 weeks. Alfacalcidol treatment resulted in elevated 1,25D serum levels. This was accompanied by hypercalcaemia and a reduction in body mass, the latter largely attributable to a reduced food intake. However, kidney function, as reflected by normal creatinine serum levels, as well as heart mass were unaffected. The 17% reduction in maximal isometric force and power was explicable by a similar loss of muscle mass. The force-frequency relationship of the 6-week-treated old rats was shifted to the left, but neither the shape of the force-velocity relationship nor the fatigability of the muscle were altered. Supra-physiological doses of vitamin D were accompanied by significant reductions in body and muscle mass, but not by an improvement in muscle functioning. Weight loss was largely due to a reduced food intake, while the left shift in the force-frequency relation may be due to increased 1,25D levels.
Journal of physiology and pharmacology: an official journal of the Polish Physiological Society 02/2011; 62(1):111-8. · 2.27 Impact Factor
-
Journal of musculoskeletal & neuronal interactions 12/2010; 10(4):245-8. · 2.00 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Oxidation alters calcium sensitivity, and decreases maximum isometric force (Po) and shortening velocity (Vmax) of single muscle fibres. To examine the effect of oxidation on the curvature of the force-velocity relationship, which determines muscle power in addition to Po and Vmax, skinned rat type I fibres were maximally activated at 15°C in a solution with pCa 4.5 and subjected to isotonic contractions before and after 4-min incubation in 50 mM H₂O₂ (n=10) or normal relaxing solution (n=3). In five oxidised and four control fibres the rate of force redevelopment (ktr), following a rapid release and re-stretch, was measured. This gives a measure of the sum of the rate constants for cross-bridge attachment (f) and detachment (g₁): (f+g₁). H₂O₂ reduced Po, Vmax and ktr by 19%, 21% and 24% respectively (P<0.001), while the shape of the force-velocity relationship was unchanged. Fitting data to the Huxley cross-bridge model suggested that oxidation decreased both the rate constant for cross-bridge attachment (f), and detachment of negatively strained cross-bridges (g₂), similar to the effect of reduced activation. This suggests that oxidative modification is a possible cause of the variation in contractile properties between muscle fibres of the same type.
Journal of musculoskeletal & neuronal interactions 12/2010; 10(4):267-73. · 2.00 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Reducing the activating calcium concentration with skinned fibres is known to decrease isometric force and maximal shortening velocity, both of which will reduce the peak power. However, power is also a function of the curvature of the force-velocity relationship, and there is limited information on how changes in activating calcium affect this important property of muscle fibres. Force-velocity relationships of permeabilized single type I fibres from rat soleus muscle were determined using isotonic contractions at 15°C with both maximal (pCa 4.5) and submaximal activation (pCa 5.6). The rate of tension redevelopment (k(tr)), which provides a measure of sum of the apparent rate constants for cross-bridge attachment and detachment (f(app) + g(app)) following a rapid release and restretch, was also measured. Compared with pCa 4.5, specific tension (P(o)) at pCa 5.6 declined by 22 ± 8% (mean ± s.d.) and the maximal velocity of shortening (V(max)) fell by 44 ± 7%, but curvature of the force-velocity relationship (a/P(o)) rose by 47 ± 31%, indicating a less concave relationship. The value of k(tr) declined by 23 ± 7%. The change in a/P(o) reduced the impact of changes in P(o) and V(max) on peak power by approximately 25%. Fitting the data to Huxley's model of cross-bridge action suggests that lower activating calcium decreased both the rate constant for cross-bridge attachment (f) and that for detachment of negatively strained cross-bridges (g(2)). The fact that V(max) (and thus g(2)) changed to a greater extent than k(tr) (f(app) + g(app)) is the reason that reduced activation results in a reduction in curvature of the force-velocity relationship.
Experimental physiology 10/2010; 96(2):171-8. · 3.17 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The present study investigated whether in vivo human quadriceps femoris (QF) muscle specific tension changed following strength training by systematically determining QF maximal force and physiological cross-sectional area (PCSA).
Seventeen untrained men (20 +/- 2 years) performed high-intensity leg-extension training three times a week for 9 weeks. Maximum tendon force (F(t)) was calculated from maximum voluntary contraction (MVC) torque, corrected for agonist and antagonist muscle activation, and moment arm length (d(PT)) before and after training. QF PCSA was calculated as the sum of the four component muscle volumes, each divided by its fascicle length. Dividing F(t) by the sum of the component muscle PCSAs, each multiplied by the cosine of the respective fascicle pennation angle, provided QF specific tension.
MVC torque and QF activation increased by 31% (P < 0.01) and 3% (P < 0.05), respectively, but there was no change in antagonist co-activation or d(PT). Subsequently, F(t) increased by 27% (P < 0.01). QF volume increased by 6% but fascicle length did not change in any of the component muscles, leading to a 6% increase in QF PCSA (P < 0.05). Fascicle pennation angle increased by 5% (P < 0.01) but only in the vastus lateralis muscle. Consequently, QF specific tension increased by 20% (P < 0.01).
An increase in human muscle specific tension appears to be a real consequence of resistance training rather than being an artefact of measuring errors but the underlying cause of this phenomenon remains to be determined.
Acta Physiologica 05/2010; 199(1):83-9. · 3.09 Impact Factor
-
H Degens
[show abstract]
[hide abstract]
ABSTRACT: Ageing is associated with a slow, but progressive muscle weakness, which is largely attributable to muscle wasting. A diminished function of satellite cells at old age may hamper preservation and repair from (contraction)-induced injury and contribute to the age-related muscle wasting. Satellite cell function may be affected by circulating factors, as muscle regeneration in old mice sharing the circulation of young mice is not impaired. Chronic low-grade systemic inflammation in old organisms may be that environmental factor. Indeed, the inflammatory cytokine tumor necrosis factor-alpha (TNFalpha) negatively affects the muscle regenerating capacity. TNFalpha destabilizes MyoD, a muscle-specific transcription factor involved in satellite cell proliferation and differentiation, and induces apoptosis of satellite cells, particularly at old age. Here it is proposed that some of these effects are mediated by TNFalpha-induced expression of inhibitors of differentiation proteins. Yet, the increase in TNFalpha during the normal inflammatory response helps, rather than impairs, the repair process. This apparent contradiction may be resolved by the fact that the effects of TNFalpha are concentration and time dependent. Thus, the negative effect of systemic inflammation on muscle strength at old age may only become apparent when it exceeds a certain threshold and persists for a prolonged period.
Scandinavian Journal of Medicine and Science in Sports 10/2009; 20(1):28-38. · 2.87 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: We have explored the extent to which the maximal velocity of unloaded shortening (V(max)), the force generated per unit cross-sectional area (P(0)) and the curvature of the force-velocity relationship (a/P(0) in the Hill equation) contribute to differences in peak power of chemically skinned single fibres from the quadriceps muscle of healthy young male subjects. The analysis was restricted to type I and IIA fibres that contained a single type of myosin heavy chain on electrophoretic separation. Force-velocity relationships were determined from isotonic contractions of maximally activated fibres at 15 degrees C. Mean (+/- s.d.) peak powers were 1.99 +/- 0.72 watts per litre (W L(-1)) for type I fibres and 6.92 +/- 2.41 W L(-1), for type IIA fibres. The most notable feature, however, was the very large, sevenfold, range of power outputs within a single fibre type. This wide range was a consequence of variations in each of the three components determining power: P(0), V(max) and a/P(0). Within a single fibre type, P(0) varied threefold, and V(max) and a/P(0) two- to threefold. There were no obvious relationships between P(0) and V(max) or between P(0) and a/P(0). However, there was a suggestion of an inverse relationship between a/P(0) and V(max), the effect being to reduce, somewhat, the impact of differences in V(max) on peak power. In searching for the causes of variation in peak power of fibres of the same type, it appears likely that there are two factors, one that affects P(0) and another that leads to variation in both V(max) and a/P(0).
Experimental physiology 08/2009; 94(10):1070-8. · 3.17 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To determine whether inhalation of carbon monoxide (CO), resulting in carboxyhaemoglobin (COHb) levels observed in smokers, had an effect on muscle fatigue during electrically evoked and voluntary muscle contractions.
Young non-smoking males inspired CO from a Douglas bag until their COHb level reached 6%. During the control condition the same participants inspired ambient air from a Douglas bag for 6 min. Fatigue was assessed as the decline in torque in isometric knee extensions, during 2 min of electrically evoked contractions (30 Hz, 1 s on, 1 s off) and during 2 min of maximal isometric voluntary contractions (1 s on, 1 s off). A fatigue index (FI) was calculated as the ratio of final torque : initial torque. Time to peak torque (TPT) and half relaxation time ((1/2)RT) were also determined for the electrically evoked contractions.
The FI during both the voluntary fatigue test (control: 0.80 +/- 0.09 vs. CO: 0.70 +/- 0.08; mean +/- SD) and that of the fatigue test with electrically evoked contractions (control: 0.61 +/- 0.09 vs. CO: 0.53 +/- 0.12) was significantly lower after CO inhalation than after inhalation of ambient air (P < 0.05). There was, however, no effect of CO on the changes in TPT or (1/2)RT during the fatigue test.
Carbon monoxide inhalation resulting in COHb levels found in smokers has an acute impact on the ability of the muscle to resist fatigue.
Acta Physiologica 03/2008; 192(3):397-401. · 3.09 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Passive stretching is commonly used to increase limb range of movement prior to athletic performance but it is unclear which component of the muscle-tendon unit (MTU) is affected by this procedure. Movement of the myotendinous junction (MTJ) of the gastrocnemius medialis muscle was measured by ultrasonography in eight male participants (20.5 +/- 0.9 years) during a standard stretch in which the ankle was passively dorsiflexed at 1 deg s(-1) from 0 deg (the foot at right angles to the tibia) to the participants' volitional end range of motion (ROM). Passive torque, muscle fascicle length and pennation angle were also measured. Standard stretch measurements were made before (pre-) and after (post-) five passive conditioning stretches. During each conditioning stretch the MTU was taken to the end ROM and held for 1 min. Pre-conditioning the extension of the MTU during stretch was taken up almost equally by muscle and tendon. Following conditioning, ROM increased by 4.6 +/- 1.5 deg (17%) and the passive stiffness of the MTU was reduced (between 20 and 25 deg) by 47% from 16.0 +/- 3.6 to 10.2 +/- 2.0 Nm deg(-1). Distal MTJ displacement (between 0 and 25 deg) increased from 0.92 +/- 0.06 to 1.16 +/- 0.05 cm, accounting for all the additional MTU elongation and indicating that there was no change in tendon properties. Muscle extension pre-conditioning was explicable by change in length and pennation angle of the fascicles but post-conditioning this was not the case suggesting that at least part of the change in muscle with conditioning stretches was due to altered properties of connective tissue.
The Journal of Physiology 02/2008; 586(1):97-106. · 4.72 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: In literature, an inconsistency exists in the submaximal exercise intensity at which type II fibers are activated. In the present study, the recruitment of type I and II fibers was investigated from the very beginning and throughout a 45-min cycle exercise at 75% of the maximal oxygen uptake, which corresponded to 38% of the maximal dynamic muscle force. Biopsies of the vastus lateralis muscle were taken from six subjects at rest and during the exercise, two at each time point. From the first biopsy single fibers were isolated and characterized as type I and II, and phosphocreatine-to-creatine (PCr/Cr) ratios and periodic acid-Schiff (PAS) stain intensities were measured. Cross sections were cut from the second biopsy, individual fibers were characterized as type I and II, and PAS stain intensities were measured. A decline in PCr/Cr ratio and in PAS stain intensity was used as indication of fiber recruitment. Within 1 min of exercise both type I and, although to a lesser extent, type II fibers were recruited. Furthermore, the PCr/Cr ratio revealed that the same proportion of fibers was recruited during the whole 45 min of exercise, indicating a rather constant recruitment. The PAS staining, however, proved inadequate to fully demonstrate fiber recruitment even after 45 min of exercise. We conclude that during cycling exercise a greater proportion of type II fibers is recruited than previously reported for isometric contractions, probably because of the dynamic character of the exercise. Furthermore, the PCr/Cr ratio method is more sensitive in determining fiber activation than the PAS stain intensity method.
Journal of Applied Physiology 12/2007; 103(5):1752-6. · 3.75 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: To determine whether muscle function is compromised in healthy smokers in comparison with activity-matched non-smokers.
Nine male smokers (aged 22.2 +/- 2.5 years: mean +/- SD) with a smoking history of 2.5 +/- 3.1 pack years, and ten male control participants (25.4 +/- 2.9 years) matched for physical activity level participated in this study. Knee extensor strength was measured using isometric maximal voluntary contractions. Voluntary activation of the quadriceps and co-activation of the biceps femoris were determined using interpolated twitches and surface electromyography respectively. The frequency-torque relationship and fatigue resistance were assessed with electrically evoked contractions. A fatigue index was determined as the ratio of final torque to initial torque during a series of isometric contractions (2 min; 30 Hz; 1 s contraction/1 s rest). Quadriceps anatomical cross sectional area was measured with MRI at 50% of femur length.
Maximal voluntary contraction torque, quadriceps anatomical cross sectional area, knee extensor torque/quadriceps cross sectional area, activation, co-activation and force-frequency relationship were similar, whereas the fatigue index was 17% lower in smokers than non-smokers.
In young men smoking does not significantly affect quadriceps muscle mass and contractile properties, but does reduce fatigue resistance of the quadriceps muscle, which was not attributable to differences in physical activity.
Acta Physiologica 11/2007; 191(2):123-9. · 3.09 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Skeletal muscle is a highly plastic tissue. For example, muscle hypertrophies during strength training and increases its oxidative capacity in response to endurance training. Conditions associated with disuse, however, are also accompanied by adaptations, of which atrophy and a slow-to-fast transition are most prominent. Fast and slow muscles respond differently to disuse. The different response of muscle to different models of disuse reveals that loading is most important, but that also activity level, neurotrophic factors, and ageing play a part in determining the mass, morphology, contractile properties, and fatigability of a muscle. Muscle loss during disuse is a result, at least in part, of apoptosis. Finally, skeletal muscle wasting and remodelling during ageing and chronic disorders, such as chronic heart failure and chronic obstructive pulmonary disease, are not entirely attributable to disuse, but are also related to secondary consequences of the disease, most notably inflammation. Besides activating other pathways, we present evidence that inflammation during ageing and chronic disorders causes muscle wasting via alterations in abundance and/or activity of muscle specific transcription factors and induction of apoptosis, and that systemic inflammation rather than disuse is the primary cause of muscle wasting during ageing and chronic disorders.
International Journal of Sports Medicine 03/2006; 27(2):94-9. · 2.43 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA, protein, and enzyme activity levels in hindlimb muscles of adult and senescent Fischer 344 x Brown Norway rats were investigated. Soleus muscles from adult and senescent rats had similar levels of GAPDH. In contrast, muscles containing a large proportion of glycolytic fibers had lower GAPDH levels in senescent rats relative to these muscles in adult rats; this was observed at both the mRNA and protein levels. These data indicate that skeletal muscle glycolytic capacity of fast muscles is diminished with age and that it may be caused by changes at the level of transcription. Also, because GAPDH mRNA levels change with age in several rat muscles, GAPDH mRNA is not always a proper internal control for mRNA analyses of aging skeletal muscle.
The Journals of Gerontology Series A Biological Sciences and Medical Sciences 04/2000; 55(3):B160-4. · 4.60 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: This review summarizes the effects of altered thyroid hormone levels on the expression of myosin isoforms and contractility in single muscle fibres from fast- and slow-twitch muscles from young and old male and female rats. The differences between male and female hyperthyroid soleus muscles are suggested to be related to an interaction of thyroid hormones and sex hormones in the regulation of myosin gene expression. Additionally, the mismatch between the protein and mRNA levels of MyHCs between male and female hyperthyroid extensor digitorum longus (EDL) muscles raises the possibility of a gender-related difference in post-transcriptional, translational or post-translational regulation of MyHC isoforms by T3.
Acta Physiologica Scandinavica 01/2000; 167(4):313-6. · 2.55 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Surgery and accidental trauma are associated with a transient period of insulin resistance, substrate catabolism and muscle weakness. In the present study, we evaluated the changes in the force-generating capacity of chemically skinned single muscle fibres following abdominal surgery. Biopsies of the m. vastus lateralis were obtained in three patients 1 day before and 3 or 6 days after surgery. Part of the biopsy was frozen for histochemical analysis of the fibre cross-sectional area (FCSA) and myofibrillar protein content, and another part was used for single-fibre contractile measurements. All patients developed insulin resistance following surgery. The maximum velocity of unloaded shortening of single muscle fibres did not change following surgery. The FCSA did not decrease after surgery, as determined either from histochemical sections or from single fibres measured at a fixed sarcomere length of 2.76+/-0.09 microm (mean+/-S.D.). Further, the force-generating capacity of the single fibres, measured as maximal Ca(2+)-activated force (P(0)) or as P(0) normalized to FCSA (specific tension), remained unchanged, as did the myofibrillar protein content of the muscle. In conclusion, the muscle weakness associated with post-operative insulin resistance is not related to a decreased specific tension or a loss of myofibrillar proteins. Other potential cellular mechanisms underlying post-operative weakness are discussed.
Clinical Science 11/1999; 97(4):449-55. · 4.61 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The effects of 4 weeks of thyroid hormone (3,5,3'-triiodothyronine, T3) treatment on the myosin isoform composition and maximum velocity of unloaded shortening (V0) of single soleus muscle fibres of young (3-6 months) and old (20-24 months) female (149 fibres) and male (200 fibres) rats were studied. Gender-related differences in the up-regulation of fast myosin heavy chain (MyHC) and myosin light chain (MyLC) isoforms were observed. In the female hyperthyroid rats, pure type I fibres and fibres co-expressing type I and type IIA MyHC (type I/IIA fibres) predominated. Some fibres expressed an alpha cardiac-like MyHC isoform either purely (alpha cardiac-like fibre type) or in co-expression with IIA MyHC (alpha cardiac-like/IIA fibre type). In the male hyperthyroid rats, on the other hand, all fibres were either type I/IIA or type I/IIAX. The relative quantities of fast MyLC isoforms in type I/IIA and type I/IIAX fibres was higher in female than in male hyperthyroid rats. V0 was similar in male and female control rats, and decreased with age in both genders (P<0.001). After T3 treatment, the average V0 increased (P<0.001) in females with a concomitant up-regulation of fast MyHC and fast MyLC isoforms irrespective of age. The average V0 of the pooled fibres was higher (P<0.001) in female than in male hyperthyroid rats at both ages. In conclusion, gender- and age-related differences were observed in the regulatory influence of 4 weeks' T3 treatment on myosin isoform composition and V0 in soleus fibres. These differences are presumably related to an interaction of thyroid and sex hormones in the regulation of myosin gene expression.
Pflügers Archiv - European Journal of Physiology 01/1999; 437(1):21-30. · 4.46 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Mobilisation of the latissimus dorsi muscle as a functional graft necessarily involves division of perforating arteries that enter the distal portion of the muscle, rendering it vulnerable to ischaemic damage when the muscle is stimulated electrically. Using a fluorescent microsphere technique we showed that the blood flow contributed by the thoracodorsal artery decreases in a proximal-to-distal direction, and that of the perforating arteries in a distal-to-proximal direction, but for neither does the flow decline to zero. This is consistent with earlier reports of anastomotic connections between the 2 arterial territories. We went on to use fluorescence microscopy to demonstrate the existence of these vascular anastomoses, the first such evidence obtained under physiological conditions of pressure and flow. In clinical applications, the existence of anastomotic connections offers the prospect of maintaining flow to the distal part of the grafted muscle without the delays inherent in neovascularisation procedures.
Journal of Anatomy 08/1998; 193 ( Pt 1):93-104. · 2.37 Impact Factor