Disease relevance of Quadriceps Muscle

• We measured pCO(2) in the rectus femoris muscle during local stimulation with 500 microL caffeine 80 mmol/L in 12 patients susceptible to malignant hyperthermia, eight non-susceptible individuals, and seven healthy controls [1].
• We conclude that in human disease states characterized by insulin resistance, i.e., obesity, IGT, NIDDM, and GDM, GLUT4 gene expression is normal in vastus lateralis or rectus abdominis [2].
• We have recently shown that patients with chronic obstructive pulmonary disease (COPD) develop contractile fatigue of their quadriceps muscle following endurance exercise [3].
• Needle biopsies obtained from vastus lateralis muscle from 20 patients with noninsulin-dependent diabetes mellitus (NIDDM) and 20 normal control subjects were analyzed for the relative expression of insulin receptor mRNA variants in a novel assay using fluorescence-labeled primers and subsequent analysis on an automated DNA sequencer [4].
• Twenty-eight male patients with ischaemic heart disease (IHD) performed OBLA (onset of blood lactate accumulation) exercise stress tests and had muscle biopsies taken from their vastus lateralis muscle the day before coronary bypass grafting [5].

Psychiatry related information on Quadriceps Muscle

• The aim of the study was to investigate the effects of oral L-carnitine supplementation on pain (VAS scale), tenderness (pain thresholds) and CK release induced by a 20-min eccentric effort of the quadriceps muscle [6].
• METHODS: The maximal isometric voluntary strength and fatigability were determined in hand-grip and quadriceps muscles from nine male COPD patients (FEV(1) 30-50% predicted) and control subjects matched for fat-free mass (FFM), physical activity level and age [7].

High impact information on Quadriceps Muscle

• In additional studies, vastus lateralis muscle was obtained by percutaneous biopsy during basal and insulin-stimulated conditions for assay of hexokinase and citrate synthase, and for immunohistochemical labeling of Glut 4 [8].
• HKII contributes with about one-third of total HK activity in a supernatant of human vastus lateralis muscle [9].
• Insulin receptor function and glycogen synthase (GS) activity and expression were examined in biopsies of vastus lateralis muscle [10].
• Analysis of biopsies of quadriceps muscle from 19 NIDDM patients and 19 control subjects showed in the basal state a 30% decrease (P < 0.005) in total GS activity and a 38% decrease (P < 0.001) in GS mRNA/microgram DNA in NIDDM patients, whereas the GS protein level was normal [11].
• Low-intensity exercise was not associated with a change in muscle (vastus lateralis) carnitine metabolism [12].

Chemical compound and disease context of Quadriceps Muscle

• In a cross-sectional study we have examined the regulatory effect of insulin in vivo on the major insulin regulatable glucose transporter (GLUT4) in vastus lateralis muscle from 12 noninsulin-dependent diabetes mellitus (NIDDM) patients and 8 healthy control subjects [13].
• Expression and carbonylation of creatine kinase in the quadriceps femoris muscles of patients with chronic obstructive pulmonary disease [14].
• Nitric oxide synthases and protein oxidation in the quadriceps femoris of patients with chronic obstructive pulmonary disease [15].
• Palmitate oxidation capacity and content of fatty acid-binding protein were determined in liver, heart and quadriceps muscle from rats with 2-week streptozotocin-induced diabetes mellitus and controls [16].
• MEASUREMENTS AND MAIN RESULTS: After 30 mins of aortic clamping, angiotensinogen, angiotensin type 1 receptor, angiotensin-converting enzyme, and interleukin-6 genes were all overexpressed at RT-PCR studies in quadriceps muscle of patients undergoing aortic abdominal aneurysm repair, and the overexpression persisted after reperfusion [17].

Biological context of Quadriceps Muscle

• Reduced (GSH) and oxidized (GSSG) glutathione, lipid peroxidation, and gamma-glutamyl cysteine synthase heavy subunit chain mRNA expression (gammaGCS-HS mRNA) were measured in the vastus lateralis [18].
• These results indicate adaptation in the form of augmented glycolysis (PFK), and decreased aerobic metabolism (CS) in the quadriceps femoris muscle in patients with advanced COPD [19].
• To investigate this possibility, we obtained quadriceps femoris biopsies in 15 patients with COPD (8 with normal body mass index [BMI] and 7 with low [< 20 kg/m(2)] BMI), 8 healthy volunteers, and 6 sedentary subjects undergoing orthopedic surgery (both groups with normal BMI) [20].
• Both CAPON and utrophin protein levels increased in dystrophic quadriceps muscle after treatment with the steroid deflazacort plus L-arginine, known to reduce the dystrophic phenotype [21].
• Phosphorylation of p70S6K (P = 0.443) and 4E-BP1 (P = 0.192) was not increased in either muscle; however, the soleus contained more total (P = 0.002) and phosphorylated (P = 0.013) 4E-BP1 than the vastus lateralis [22].

Anatomical context of Quadriceps Muscle

• Therefore, an elevated corticosteroid production did not account for the wasting of body fat, lean body mass, skeletal muscle proteins, or decreased RNA activity in quadriceps muscles from tumor-bearing animals, although such muscles were sensitive to physiologic doses of injected hydrocortisone (20 micrograms/day) [23].
• Histochemical analysis showed co-localization of LacZ and dystrophin expression in 5% of soleus and quadriceps muscle fibres and in 4% of heart myocytes of two of seven 8-week-old treated mdx mice [24].
• Human satellite cells were isolated from the quadriceps muscles of three CDM fetuses with different clinical severity [25].
• Fractional muscle protein synthesis was determined by measuring the increment of 13C leucine in mixed skeletal muscle protein obtained by needle biopsy from the quadriceps muscle during a primed-continuous infusion of L-(1-13C) leucine [26].
• The dose-response characteristics of several glucose-utilizing tissues (brain, heart, white adipose tissue, brown adipose tissue, and quadriceps muscle) to a single injection of insulin have been compared in control mice and mice made obese with a single injection of gold thioglucose (GTG) [27].

Associations of Quadriceps Muscle with chemical compounds

• As a marker of insulin action, the percentage of total glycogen synthase present in the I form (glucose-6-phosphate independent) was measured in quadriceps muscle biopsies [28].
• We have compared the capillary density and muscle fiber type of musculus vastus lateralis with in vivo insulin action determined by the euglycemic clamp (M value) in 23 Caucasians and 41 Pima Indian nondiabetic men [29].
• In group A, vastus lateralis white muscle, which contained predominantly fast glycolytic fibers, showed a significant increase in protein catabolic rates compared with pair fed controls (0.95 +/- 0.05 nmol tyrosine released.mg-1.2 h-1 vs. 0.86 +/- 0.04; P less than 0.05) [30].
• Confocal laser-scanning and digital fluorescence imaging microscopy were used to quantify the mitochondrial autofluorescence changes of NAD(P)H and flavoproteins in unfixed saponin-permeabilized myofibers from mice quadriceps muscle tissue [31].
• Here we report increases in vastus lateralis muscle mitochondrial ATP production capacity (32-42%) in healthy humans (P < 0.01) i.v. infused with insulin (1.5 milliunits/kg of fat-free mass per min) while clamping glucose, amino acids, glucagon, and growth hormone [32].

Gene context of Quadriceps Muscle

• Biopsy of vastus lateralis muscle was used to measure cytochrome c oxidase (COX) enzyme activity and UCP2 content [33].
• We have confirmed that a 10-fold increase in UCP3 mRNA levels occurs in rat quadriceps muscle between 12 and 24 h of food removal [34].
• CONCLUSION: In sedentary, clinically stable maintenance hemodialysis patients as compared to sedentary normal individuals, the mRNA levels for IGF-IEa, IGF-II, and the IGF-I receptor are decreased in vastus lateralis muscle [35].
• Unexpectedly, Mstn(-/-) mice lost more body (13%, P < 0.05) and quadriceps femoris (17%, P < 0.05) mass than wild-type mice and lost 33% of EDL mass (P < 0.01) after HS [36].
• In addition, radiographs of mice injected with hBMP-2 showed that much of the quadriceps muscle had undergone mineralization by day 14 [37].

Analytical, diagnostic and therapeutic context of Quadriceps Muscle

• Subjects received an oral glucose tolerance test (OGTT) and 120-min euglycemic insulin (80 mU/m2 per min) clamp with 3-[3H]glucose/vastus lateralis muscle biopsies to quantitate rates of insulin-mediated whole-body glucose disposal (Rd) and intramyocellular LCFA-CoAs before and after acipimox (250 mg every 6 h for 7 days) [38].
• The percentage of IR-RNA molecules without exon 11, encoding the high-affinity isoform, was determined by cDNA-mediated PCR amplification of RNA extracts from the quadriceps femoris muscle of healthy control subjects (n = 9) and NIDDM patients (n = 7) [39].
• Under local anesthesia, approximately 1 g of vastus lateralis muscle was obtained from six healthy subjects before and 60 min after ingestion of a 75-g glucose load [40].
• To accomplish this, we used the glucose clamp technique with isotopic determination of glucose disposal and indirect calorimetry for measuring the pathways of glucose metabolism, and vastus lateralis muscle biopsies to determine the effects of insulin on glycogen synthase and PDH activities [41].
• 2. HDC activity in the quadriceps femoris muscle was markedly elevated following contractions evoked by even a few minutes of direct electrical stimulation, peaking at 8-12 h following contraction lasting 10 min, and gradually decreasing during the 24 h following contraction [42].

References