Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “PECTORALIS MUSCLES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 613 records · Page 34Linked to original sources
PubMed1994

The metabolic characteristics of the locomotory muscles of grey seals (Halichoerus grypus), harbour seals (Phoca vitulina) and Antarctic fur seals (Arctocephalus gazella).

It is not known precisely how marine mammals are able to maintain muscle function during active swimming in breath-hold dives, when ventilation stops and heart rate falls. Examination of muscle biochemistry and histochemistry can provide information on the relative importance of different metabolic pathways, the contractile potential of the muscle fibres, the oxygen storage capacity of the muscle and the capillary distribution in these animals. In this study, samples of locomotory muscle were taken from wild grey seals (Halichoerus grypus), harbour seals (Phoca vitulina) and Antarctic fur seals (Arctocephalus gazella); Wistar rat muscle was analysed for comparative purposes. Activities of citrate synthase and beta-hydroxyacyl CoA dehydrogenase were higher in the harbour seal muscle than in the grey seal muscle, suggesting that harbour seals have a greater aerobic capacity. Both phocid muscles had a greater reliance on fatty acid oxidation than the fur seal or rat muscles. The myoglobin data demonstrate that the grey seals have the highest oxygen storage capacity of the three pinniped species, which correlates with their greater diving ability. Myoglobin levels were higher in all three pinniped species than in the Wistar rat. The fibre type compositions suggest that the muscles from the fur seals have higher glycolytic capacities than those of the phocid seals [fur seal pectoralis, 7% slow-twitch oxidative fibres (SO), 25% fast-twitch oxidative glycolytic fibres (FOG), 68% fast-twitch glycolytic fibres (FG); grey seal 57% SO, 5% FOG, 38% FG; area per cents]. However, the pectoralis muscle of the fur seal, although the most glycolytic of the pinniped muscles studied, has the highest capillary density, which indicates a high capacity for fuel distribution. These results show that, while pinniped muscle has an increased oxygen storage potential compared with the muscle of a typical terrestrial mammal, there are no distinct adaptations for diving in the enzyme pathways or fibre type distributions of the pinniped muscle. However, the muscle characteristics of each species can be related to its diving behaviour and foraging strategy.

3-Hydroxyacyl CoA Dehydrogenases↗
PubMed1979

Stereologic analysis of dystrophic chicken muscle.

Stereologic methods have been used to estimate the volume and surface densities of sarcoplasmic reticulum (SR) and T tubules of normal and dystrophic chicken pectoralis muscle fibers. The surface and volume densities of the T system in dystrophic muscle fibers showed large increases compared with normal muscle fibers; the surface and volume densities of the SR showed large decreases. In addition, the SR and T system in dystrophic fibers undergo changes in shape. The tubules of the free SR become much narrower; the T system becomes dilated and vesiculated. Dystrophic fibers, on the average, are much larger than normal but maintain the same sarcolemmal surface/fiber volume ratio as normal fibers. Alterations in the surface and volume densities of the dystrophic sarcotubular system may account for some of the altered contractile properties of these muscles.

Animals↗
PubMed1983

Effects of environmental lead poisoning on the breast muscle of the Canada goose: an ultrastructural study.

Canada geese (Branta canadensis) showing symptoms of lead poisoning were collected from their natural habitat, and their pectoralis muscle was examined for ultrastructural changes. Both the red and white fibre types showed pathological changes. In some red fibres, there were prominent accumulations of glycogen granules, occasionally membrane-bound, at certain spots, and of lipid droplets. Glycogen and lipid were also located within mitochondria. When lipid droplets were sparse in a certain fibre, occurrence of fused mitochondria often with distorted cristae, was observed. Swollen mitochondria with disrupted cristae and dense intramitochondrial inclusions were present. Lysosomes and areas of mitochondrial degeneration were also seen. Dilatation of the terminal cisternae of the sacroplasmic reticulum and of the T-system was also observed in the red fibres. In the white fibres, enormous accumulations of glycogen granules were present and the cristae of mitochondria were often disrupted. In some white fibres the triads and Z-lines were in a state of severe disarray. The nuclei in both the fibre types appeared to be normal and did not contain the typical intranuclear inclusion bodies present in kidney and liver cells of lead poisoned animals and humans. It is suggested that, in the goose, lead has a diabetogenic effect, which in the breast muscle, is manifested in the large accumulations of glycogen and the disruption of glycolytic metabolism. Lead poisoning also affects mitochondrial structure and function leading to adverse effects on oxidative metabolism in the muscle.

Animals↗
PubMed1998

Primary peptide sequences from squid muscle and optic lobe myosin IIs: a strategy to identify an organelle myosin.

The squid giant axon provides an excellent model system for the study of actin-based organelle transport likely to be mediated by myosins, but the identification of these motors has proven to be difficult. Here the authors purified and obtained primary peptide sequence of squid muscle myosin as a first step in a strategy designed to identify myosins in the squid nervous system. Limited digestion yielded fourteen peptides derived from the muscle myosin which possess high amino acid sequence identities to myosin II from scallop (60-95%) and chick pectoralis muscle (31-83%). Antibodies generated to this purified muscle myosin were used to isolate a potential myosin from squid optic lobe which yielded 11 peptide fragments. Sequences from six of these fragments identified this protein as a myosin II. The other five sequences matched myosin II (50-60%, identities), and some also matched unconventional myosins (33-50%). A single band that has a molecular weight similar to the myosin purified from optic lobe copurifies with axoplasmic organelles, and, like the optic lobe myosin, this band is also recognized by the antibodies raised against squid muscle myosin II. Hence, this strategy provides an approach to the identification of a myosin associated with motile axoplasmic organelles.

Amino Acid Sequence↗
PubMed1980

Properties of muscles from chickens with inherited muscular dystrophy.

Inherited muscular dystrophy of the chicken is an abnormality affecting the normal development and function of fast-twitch skeletal muscles. Several different strains of dystrophic chickens have been developed by selection for high lipid content in the pectoralis muscle and early onset of the disorder or by outcrossing the original New Hampshire stock into an inbred White Leghorn breed. The purpose of this study was to determine whether fast-twitch dystrophic muscles differ in expressed properties within the same bird and to examine the differences in gene expression between dystrophic New Hampshire and White Leghorn breeds. The biochemical and physiological properties examined were lactate dehydrogenase and acetylcholinesterase activities, total lipid content, muscle fiber diameter and electromyographic insertion activity. Results showed that fiber diameter and lipid levels were different in muscles within individual birds of two dystrophic lines and that the dystrophic gene causes rapid fiber atrophy and high lipid content in the White Leghorn breed. In addition, differences in lactate dehydrogenase activity and electromyographic patterns were found between two dystrophic lines. The results suggest that the expressed properties differ within each muscle of the dystrophic bird and that the expression of the dystrophic genes is dependent upon the nature of the genetic background of the breed.

Acetylcholinesterase↗
PubMedDate not supplied

Comparative development in captive and migratory populations of the barnacle goose.

The development of the locomotory muscles and associated skeletal structures of goslings and adults from a captive population of barnacle geese (Branta leucopsis) was compared with that from a wild migratory population. There was no significant difference between flight-muscle development of wild and captive goslings up to 7 wk of age, when the birds are first able to fly. In contrast, mass-specific citrate-synthase activity in the semimembranosus leg muscle of the captive goslings was significantly lower than that of wild goslings by 5 wk of age. During the postfledging premigratory period, captive geese showed significantly higher values for both mass and mass-specific citrate-synthase activity of the leg muscles than those of wild birds. Premigratory wild geese had significantly higher citrate-synthase activity in the pectoralis muscles and larger cardiac ventricular mass (by ca. 20%-25%) than both wild postmoulting and captive premigratory adults. Total flight-muscle mass was only slightly reduced (by ca. 10%) in long-term captive adults compared with wild premigratory adults. Most of the differences between these two populations appear primarily to reflect their relative levels of activity and/or differences in their ambient environment, rather than any intrinsic differences in developmental or adult physiology.

Animals↗
PubMed2006

Latissimus dorsi breast reconstruction utilizing functional muscle transfer and tissue expansion.

Latissimus dorsi breast reconstruction with implants has been criticized for Baker III or IV capsular contractures in as many as 30% of patients. Also criticized is muscle atrophy and loss of breast volume and definition. This study evaluated 2 modifications of the classic latissimus reconstruction: muscle transferred as an innervated functional unit and tissue expansion posterior to the latissimus but anterior to the pectoralis muscle. After expansion, a permanent prosthesis was placed (46 silicone gel and 3 saline). Forty-nine such reconstructions were done in 32 patients (17 bilateral and 15 unilateral), with average follow-up of 19 months. Only 4 Baker III capsular contractures (8%) and no Baker IV contractures occurred. All patients demonstrated excellent retention of breast shape/definition. This study demonstrates that functional muscle transfer and tissue expansion results in low capsular contracture rates and excellent retained breast shape.

Female↗
PubMed1995

Effect of electrical stunning amperage and peri-mortem struggle on broiler breast rigor development and meat quality.

Two experiments were conducted to determine the effects of electrical stunning and peri-mortem muscle activity (struggle in and around the time of slaughter) on post-mortem biochemical reactions in broiler breast muscle (Pectoralis major). Broilers were stunned with either 50 or 125 mA or were killed without stunning. In Experiment 1 (n = 273), broilers were either physically restrained to reduce struggling during slaughter or were unrestrained and allowed to struggle freely. Breast mean pH and R-value (ratio of adenosine to inosine nucleotides) were determined at 15 min and 24 h post-mortem, and Allo-Kramer shear was determined on 48 h post-mortem cooked meat samples from muscles excised at 15 min or 24 h. In Experiment 2 (n = 65), the breast muscle was unilaterally denervated by surgically severing the Pectoralis nerve on one side and performing a sham operation on the contralateral side. Results indicated that physical restraint resulted in higher muscle pH and lower R-values at 15 min post-mortem in the unstunned birds and birds stunned at 50 mA, but had no effect on breast meat from birds stunned at 125 mA. There were no treatment effects on meat tenderness or 24-h post-mortem pH or R-values. Stunning amperage had no effect on denervated muscle pH at 15 min post-mortem, but did affect the sham-operated muscle pH and R-values as in Experiment 1. These results indicate that the main effect of electrical stunning on early rigor development may be due primarily to inhibition of peri-mortem struggle.

Animals↗
PubMed1994

Identification of a 115-kDa protein from muscle tissues: expression of a novel nonmuscle alpha-actinin in vascular endothelial cells.

A novel nonmuscle alpha-actinin from chicken lung tissue is distinct from reported nonmuscle and muscle alpha-actinins in its mobility on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in the presence of 6 M urea (apparent molecular mass is 115 kDa) and its Ca(2+)-sensitivity in actin binding (M. Imamura and T. Masaki, J. Biol. Chem. 267, 25927-25933, 1992). SDS-PAGE analysis of extract from chicken gizzard smooth muscle tissue in the presence of urea showed the existence of a protein migrating at 115 kDa. Analyses of proteolytic digestion and partial amino acid sequence revealed that the latter 115-kDa protein is identical or very similar to the Ca(2+)-insensitive lung alpha-actinin. We prepared an antibody specific for the 115-kDa protein by affinity column coupled with the purified lung alpha-actinin, and the expression and distribution of the 115-kDa protein in muscle tissues were examined. Immunoblotting and immunofluorescence microscopy demonstrated that the 115-kDa protein was expressed in heart and pectoralis muscle tissues as well as in gizzard. Double-fluorescence staining with the anti-115-kDa protein antibody and anti-muscle alpha-actinin antibody indicated that the 115-kDa protein was localized in tubular structures along the axes of muscle fibers, whose diameter was 3.5-5 microns. The tubular structure did not respond to the muscle cells. Vascular-labeling analysis with carbon dye showed that the staining with anti-115-kDa protein antibody was located along the inside of the vascular wall. These results indicated that the Ca(2+)-insensitive alpha-actinin was expressed in vascular endothelial cells and suggested that its Ca(2+)-sensitivity was related to the function of the endothelial cells.

Actinin↗
PubMed1985

Myoglobin levels and mATPase activity in pectoral muscles of spruce and ruffed grouse (Aves: Tetraoninae).

Myoglobin concentration and myosin ATPase activity were measured in the pectoral muscle of wild spruce grouse (Dendragapus canadensis) and ruffed grouse (Bonasa umbellus), together with the weight of the Mm. pectoralis, supracoracoideus and heart. mATPase activities were similar in both species, but spruce grouse contained 15 times more myoglobin in the pectoralis muscle and the heart was three times heavier than that of the ruffed grouse. The relative mass of the flight muscles and wing loading were similar between species. Characteristics of the pectoral muscle of both grouse species reflect adaptations to predation and advertising displays. The glycolytic nature of the ruffed grouse pectoral muscle and small heart size is an adaptation to a sedentary existence within a small home range. The more oxidative pectoral muscle of spruce grouse together with its larger heart are adaptations to seasonal dispersals requiring more sustained flight.

Adenosine Triphosphatases↗
PubMed1986

Cardiac and skeletal muscle myosin polymorphism.

Skeletal muscles, unlike cardiac tissue, express several myosin isozymes during development which differ in primary structure from adult myosin. Monoclonal antibodies have shown the presence of at least two embryonic myosins, followed by a post-hatch myosin that persists until the appearance of adult myosin in chicken pectoralis muscle. Although the two major cardiac isozymes differ in enzymatic activity, the avian skeletal myosin isozymes all share the same high level of ATPase activity found for adult pectoralis myosin. The functional basis for the extensive myosin polymorphism in skeletal muscles thus remains to be determined.

Adenosine Triphosphatases↗
PubMed1991

Myoblasts from fetal and adult skeletal muscle regulate myosin expression differently.

We compared the expression of myosin heavy chains in myogenic cultures prepared from fetal (embryonic Day 10) and adult (12-16 weeks) chicken pectoralis muscle using immunofluorescence with isoform-specific monoclonal antibodies. We found that the majority of fetal myocytes (differentiated myoblasts) and myotubes coexpressed ventricular and embryonic myosin heavy chains in culture. Also, when fetal cells were plated at a clonal density most clones coexpressed both ventricular and embryonic isoforms. In contrast, all adult myocytes and newly formed adult myotubes expressed just ventricular myosin, whether plated at mass or clonal densities. Within 12-24 hr of the onset of fusion, adult myotubes began to express embryonic myosin as well. Eventually, the majority of adult myotubes coexpressed both ventricular and embryonic myosin. The delay of embryonic myosin expression until after fusion was also seen in passaged adult myoblasts and in myoblasts isolated from regenerating adult muscle. The expression of embryonic myosin can be abolished by inhibiting fusion with EGTA in adult but not in fetal cultures. We conclude that both fetal and adult myotubes express ventricular and embryonic myosins but only fetal myocytes express the embryonic isoform prior to fusion. This difference in the regulation of embryonic myosin expression between fetal and adult myoblasts supports the hypothesis that these cells may represent two distinct populations of myogenic precursors.

Aging↗
PubMed1988

Transition of beta-actinin isoforms during development of chicken skeletal muscle.

We examined by means of the immunoblotting technique the transition of beta-actinin isoforms during the development of the chicken from 5 day embryo to adult. As an antigen, beta-actinin was prepared from adult chicken breast muscle (pectoralis major) and polyclonal antibody was obtained by injecting undenatured beta-actinin into a rabbit. Immunoblotting examination of breast muscle at several stages of development (except 5 day embryo, in which the whole body minus the head and limbs was examined) showed that the species of beta-actinin subunits change during development: 1) beta I is already present in 5 day embryo, whereas beta II appears only after 9 days. 2) In 5 day embryo, we found, instead of beta II, a new subunit (designated beta III) that cross-reacts with the antibody, has the apparent molecular weight of 30,000 daltons and has a slightly alkaline isoelectric point compared with beta I. The content of beta III gradually decreased and beta III completely disappeared a week after hatching. Such a type of transition of the isoforms in beta-actinin subunits is similar to that observed in other muscle proteins. The transition of beta-actinin isoforms may correlate to the organization of an I-Z-I brush, especially to the length determination of thin filaments, because the developmental stage at which beta III disappears coincides with that at which the length of thin filaments is strictly determined.

Actinin↗
PubMed1991

The primary structure of skeletal muscle myosin heavy chain: II. Sequence of the 50 kDa fragment of subfragment-1.

The complete amino acid sequence of the 50 kDa fragment of subfragment-1 from adult chicken pectoralis muscle myosin was determined. It contained 431 residues including an epsilon-N-trimethyllysine at position 346. The 431-residue sequence corresponds to the sequence of residues 206 to 639 of chicken embryonic breast muscle myosin heavy chain which was predicted from the nucleotide sequence of the cDNA by Molina et al. [Molina, M. I., Kropp, K.E., Gulick, J., & Robbins, J. (1987) J. Biol. Chem. 262, 6478-6488]. Comparing the two sequences, 23 amino acid substitutions and three deletions/insertions are recognized.

Amino Acid Sequence↗
PubMed1980

Influence of experimental hypothyroidism on chick myogenesis.

The influence on chick myogenesis of hypothyroid status induced in ovo by methimazole was histologically (number and types of muscle fibers) and biochemically studied. A single injection of methimazole induced an hypothyroid status during embryogenesis, as shown by the plasma T4 levels which were separately assayed in male and female controls and treated embryos from day 12 of incubation to day 4 after hatching. In both sexes, control plasma T4 reached a peak on day 20 of incubation, but the female values were significantly higher; plasma T4 in the treated embryos remained at a low level independently of sex. Only methimazole-treated males showed a significant increase (P less than 0.01) in the total number of fibers of the two muscles (tibialis posterior and flexor digitorum) studied. Moreover, the histochemical results on succinate dehydrogenase and myofibrillar ATPase evidenced that, of the three fiber types (alpha R, alpha W and beta R) constituting the skeletal muscles, only the alpha fibers increased significantly. Aldolase (glycolytic) and NADP isocitrate dehydrogenase (tricarboxylic acid cycle) activities, measured on the adductor and pectoralis muscles, showed a similar developmental pattern in control and treated animals, but was retarded in the latter due to a 5-day delay in hatching. It is not known whether the tissular differences were related directly to the hypothyroid status, to alterations in nervous system differentiation or, as suggested by intersexual differences, to modifications in hormonal balance.

Animals↗
PubMed1997

Acceleration of post-mortem changes in Tsaiya duck (Anas platyrhynchos) breast muscle by lactic acid marination.

1. The effect of lactic acid marination at 5 degrees C on post mortem changes in breast muscle pectoralis major of spent layer Tsaiya duck was studied. 2. Myofibrils were prepared from 0.1 M and 0.2 M lactic acid marinated muscle and control (non-marinated samples) sampled at 0, 1, 3, 7 and 14 d post mortem. 3. Changes in myofibril fragmentation index (MFI), myofibrillar proteins and Z-line structure were examined. 4. Marination of duck breast muscle in lactic acid at 5 degrees C enhanced fragmentation of myofibrils and degradation of myofibrillar proteins and Z-line structure as compared to control samples. 5. In summary, lactic acid marination at 5 degrees C can accelerate the post mortem degradation of myofibrils in Tsaiya duck breast muscle.

Actinin↗
PubMed1986

Inhibition of muscle tropomyosin polymerization by DNAse I.

Tropomyosin polymerization is inhibited by DNAse I, an endonuclease which also interacts with G-actin. A 1:4 molar ratio of DNAse I to adult chicken pectoralis muscle tropomyosin almost completely prevents the increased viscosity of tropomyosin under polymerizing ionic conditions. While G-actin binding to DNAse I inhibits the DNAse I hydrolysis of DNA, tropomyosin does not affect this enzymatic activity. G-actin-DNAse I interaction is also not altered by tropomyosin.

Actins↗
PubMed1990

Muscle-type MM creatine kinase is specifically bound to sarcoplasmic reticulum and can support Ca2+ uptake and regulate local ATP/ADP ratios.

Highly purified fractions of sarcoplasmic reticulum (SR) were prepared from chicken pectoralis muscles (Saito, A., Seiler, S., Chu, A., and Fleischer, S. (1984) J. Cell Biol. 99, 875-885) and analyzed for the presence of creatine kinase (CK). Vesicles derived from longitudinal SR contained 0.703 +/- 0.428 IU of CK/mg of (SR) protein. Immunogold localization of muscle-type MM-CK on ultrathin cryosections of muscle, after removal of soluble CK, revealed relatively strong in situ labeling of M-CK remaining bound to the M band as well as to the SR membranes. In addition, purified SR vesicles were also labeled by anti-M-CK antibodies, and the peripheral labeling was similar to that observed with anti-Ca2(+)-ATPase antibodies. Only some particulate CK enzyme was released from isolated SR membranes by EDTA/low salt buffer, and CK was resistant to extraction by 0.6 M KCl. Thus, some of the MM-CK present in muscle displays strong associative behavior to the SR membranes. The SR-bound CK was sufficient to support, in the presence of phosphocreatine plus ADP, a significant portion of the maximal in vitro Ca2+ uptake rate. The ATP regeneration potential of SR-bound CK was similar to the rate of Ca2(+)-stimulated ATP hydrolysis of isolated SR vesicles. Thus, CK bound to SR may be physiologically relevant in vivo for regeneration of ATP used by the Ca2(+)-ATPase, as well as for regulation of local ATP/ADP ratios in the proximity of the Ca2+ pump and of other ATP-requiring reactions in the excitation-contraction coupling pathway.

Adenosine Diphosphate↗