Ontogenetic changes of hindlimb muscle mass in Cabot's tragopan (Galliformes, Phasianidae) and their functional implications

2021 ◽  
Author(s):  
Lin Wang ◽  
Xinsen Wei ◽  
Xinxin Liang ◽  
Zihui Zhang
Keyword(s):  
Muscle Mass ◽  
Ontogenetic Changes ◽  
Hindlimb Muscle ◽  
Functional Implications

Metabolic responses to head-down suspension in hypophysectomized rats

1993 ◽  
Vol 75 (6) ◽  
pp. 2718-2726 ◽  
Author(s):  
C. R. Woodman ◽  
C. M. Tipton ◽  
J. Evans ◽  
J. K. Linderman ◽  
K. Gosselink ◽  
...  
Keyword(s):  
Muscle Mass ◽  
Time Course ◽  
Citrate Synthase ◽  
O2 Consumption ◽  
Hindlimb Muscles ◽  
Impaired Ability ◽  
Norepinephrine Concentration ◽  
Hindlimb Muscle ◽  
Before And After ◽  
Hypophysectomized Rats

Rats exposed to head-down suspension (HDS) exhibit reductions in maximal O2 consumption (VO2max) and atrophy of select hindlimb muscles. This study tested the hypothesis that an endocrine-deficient rat exposed to HDS would not exhibit reductions in VO2max or hindlimb muscle mass. Hypophysectomized (HYPX) and sham-operated (SHAM) rats were tested for VO2max before and after 28 days of HDS or cage control (CC) conditions. No significant reductions in VO2max were observed in HYPX rats. In contrast, SHAM-HDS rats exhibited a significant reduction in absolute (-16%) and relative (-29%) measures of aerobic capacity. Time course experiments revealed a reduction in VO2max in SHAM-HDS rats within 7 days, suggesting that cardiovascular adjustments to HDS occurred in the 1st wk. HDS was associated with atrophy of the soleus (-42%) in SHAM rats, whereas HYPX rats exhibited atrophy of the soleus (-36%) and plantaris (-13%). SHAM-HDS rats had significantly lower (-38%) soleus citrate synthase activities per gram muscle mass than SHAM-CC, but no significant differences existed between HYPX-HDS and -CC rats. HDS rats had an impaired ability to thermoregulate, as indicated by significantly greater temperature increases per unit run time, compared with their CC counterparts. Pretreatment plasma epinephrine levels were significantly lower in HYPX than in SHAM rats. Norepinephrine concentration was similar for all groups except HYPX-HDS, in which it was significantly higher. HDS had no significant effect on thyroxine or triiodothyronine. SHAM-HDS rats had significantly lower concentrations of testosterone and growth hormone.(ABSTRACT TRUNCATED AT 250 WORDS)

Denervation-induced skeletal muscle atrophy is associated with increased mitochondrial ROS production

2007 ◽  
Vol 293 (3) ◽  
pp. R1159-R1168 ◽  
Author(s):  
Florian L. Muller ◽  
Wook Song ◽  
Youngmok C. Jang ◽  
Yuhong Liu ◽  
Marian Sabia ◽  
...  
Keyword(s):  
Muscle Mass ◽  
Muscle Atrophy ◽  
Common Factor ◽  
Skeletal Muscle Atrophy ◽  
Ros Generation ◽  
Ros Production ◽  
Muscle Mitochondria ◽  
Mitochondrial Ros ◽  
Hindlimb Muscle ◽  
Old Mice

Reactive oxygen species (ROS), especially mitochondrial ROS, are postulated to play a significant role in muscle atrophy. We report a dramatic increase in mitochondrial ROS generation in three conditions associated with muscle atrophy: in aging, in mice lacking CuZn-SOD ( Sod1−/−), and in the neurodegenerative disease, amyotrophic lateral sclerosis (ALS). ROS generation in muscle mitochondria is nearly threefold higher in 28- to 32-mo-old than in 10-mo-old mice and is associated with a 30% loss in gastrocnemius mass. In Sod1−/− mice, muscle mitochondrial ROS production is increased >100% in 20-mo compared with 5-mo-old mice along with a >50% loss in muscle mass. ALS G93A mutant mice show a 75% loss of muscle mass during disease progression and up to 12-fold higher muscle mitochondrial ROS generation. In a second ALS mutant model, H46RH48Q mice, ROS production is approximately fourfold higher than in control mice and is associated with a less dramatic loss (30%) in muscle mass. Thus ROS production is strongly correlated with the extent of muscle atrophy in these models. Because each of the models of muscle atrophy studied are associated to some degree with a loss of innervation, we were interested in determining whether denervation plays a role in ROS generation in muscle mitochondria isolated from hindlimb muscle following surgical sciatic nerve transection. Seven days postdenervation, muscle mitochondrial ROS production increased nearly 30-fold. We conclude that enhanced generation of mitochondrial ROS may be a common factor in the mechanism underlying denervation-induced atrophy.

scholarly journals Fine Mapping of "Mini-Muscle," a Recessive Mutation Causing Reduced Hindlimb Muscle Mass in Mice

2008 ◽  
Vol 99 (6) ◽  
pp. 679-687 ◽  
Author(s):  
J. Hartmann ◽  
T. Garland ◽  
R. M. Hannon ◽  
S. A. Kelly ◽  
G. Munoz ◽  
...  
Keyword(s):  
Muscle Mass ◽  
Fine Mapping ◽  
Recessive Mutation ◽  
Hindlimb Muscle

scholarly journals Rates of myogenesis and myofiber numbers are reduced in late gestation IUGR fetal sheep

2020 ◽  
Vol 244 (2) ◽  
pp. 339-352
Author(s):  
Eileen I Chang ◽  
Paul J Rozance ◽  
Stephanie R Wesolowski ◽  
Leanna M Nguyen ◽  
Steven C Shaw ◽  
...  
Keyword(s):  
Muscle Mass ◽  
Cross Section ◽  
Biceps Femoris ◽  
Late Gestation ◽  
Combined Processes ◽  
Entire Cross Section ◽  
Fetal Sheep ◽  
Ambient Temperatures ◽  
Hindlimb Muscle ◽  
Flexor Digitorum

Intrauterine growth-restricted (IUGR) fetuses are born with reduced skeletal muscle mass. We hypothesized that reduced rates of myogenesis would contribute to fewer and smaller myofibers in IUGR fetal hindlimb muscle compared to the normally growing fetus. We tested this hypothesis in IUGR fetal sheep with progressive placental insufficiency produced by exposing pregnant ewes to elevated ambient temperatures from 38 to 116 days gestation (dGA; term = 147 dGA). Surgically catheterized control (CON, n = 8) and IUGR (n = 13) fetal sheep were injected with intravenous 5-bromo-2′-deoxyuridine (BrdU) prior to muscle collection (134 dGA). Rates of myogenesis, defined as the combined processes of myoblast proliferation, differentiation, and fusion into myofibers, were determined in biceps femoris (BF), tibialis anterior (TA), and flexor digitorum superficialis (FDS) muscles. Total myofiber number was determined for the entire cross-section of the FDS muscle. In IUGR fetuses, the number of BrdU+ myonuclei per myofiber cross-section was lower in BF, TA, and FDS (P < 0.05), total myonuclear number per myofiber cross-section was lower in BF and FDS (P < 0.05), and total myofiber number was lower in FDS (P < 0.005) compared to CON. mRNA expression levels of cyclins, cyclin-dependent protein kinases, and myogenic regulatory factors were lower (P < 0.05), and inhibitors of the cell cycle were higher (P < 0.05) in IUGR BF compared to CON. Markers of apoptosis were not different in IUGR BF muscle. These results show that in IUGR fetuses, reduced rates of myogenesis produce fewer numbers of myonuclei, which may limit hypertrophic myofiber growth. Fewer myofibers of smaller size contribute to smaller muscle mass in the IUGR fetus.

scholarly journals Effect of Meal Timing after Resistance Exercise on Hindlimb Muscle Mass and Fat Accumulation in Trained Rats.

1999 ◽  
Vol 45 (4) ◽  
pp. 401-409 ◽  
Author(s):  
Masashige SUZUKI ◽  
Tatsuya DOI ◽  
Sang Jik LEE ◽  
Koji OKAMURA ◽  
Seiichi SHIMIZU ◽  
...  
Keyword(s):  
Resistance Exercise ◽  
Muscle Mass ◽  
Fat Accumulation ◽  
Hindlimb Muscle ◽  
Meal Timing

Ontogenetic changes in characteristics required for endothermy in juvenile black skipjack tuna (Euthynnus lineatus)

2000 ◽  
Vol 203 (20) ◽  
pp. 3077-3087 ◽  
Author(s):  
K.A. Dickson ◽  
N.M. Johnson ◽  
J.M. Donley ◽  
J.A. Hoskinson ◽  
M.W. Hansen ◽  
...  
Keyword(s):  
Muscle Mass ◽  
Heat Production ◽  
Citrate Synthase ◽  
Specific Activity ◽  
Production Capacity ◽  
Fork Length ◽  
Minimum Size ◽  
Skipjack Tuna ◽  
Ontogenetic Changes ◽  
Red Muscle

To characterize better the development of endothermy in tunas, we assessed how the abilities to generate heat and to conserve heat within the aerobic, slow-twitch (red) myotomal muscle using counter-current heat exchangers (retia) change with size in juvenile black skipjack tuna (Euthynnus lineatus) above and below the hypothesized minimum size for endothermy of 207 mm fork length (FL). Early juvenile scombrids (10–77 mm FL) collected off the Pacific coast of Panama were raised to larger sizes at the Inter-American Tropical Tuna Commission Laboratory at Achotines Bay, Panama. Evidence of central and lateral rete blood vessels was found in E. lineatus as small as 95.9 mm FL and 125 mm FL, respectively. In larger E. lineatus juveniles (up to 244 mm FL), the capacity for heat exchange increased with fork length as a result of increases in rete length, rete width and the number of vessel rows. The amount (g) of red muscle increased exponentially with fork length in both E. lineatus (105–255 mm FL) and a closely related ectothermic species, the sierra Spanish mackerel Scomberomorus sierra (151–212 mm FL), but was greater in E. lineatus at a given fork length. The specific activity (international units g(−)(1)) of the enzyme citrate synthase in red muscle, an index of tissue heat production potential, increased slightly with fork length in juvenile E. lineatus (84. 1–180 mm FL) and S. sierra (122–215 mm FL). Thus, total red muscle heat production capacity (red muscle citrate synthase activity per gram times red muscle mass in grams) increased with fork length, primarily because of the increase in red muscle mass. Below 95.9 mm FL, E. lineatus cannot maintain red muscle temperature (T(m)) above the ambient water temperature (T(a)) because juveniles of this size lack retia. Above 95.9 mm FL, the relationship between T(x) (T(m)-T(a)) and FL for E. lineatus diverges from that for the ectothermic S. sierra because of increases in the capacities for both heat production and heat retention that result in the development of endothermy.

Maximal oxygen consumption in relation to subordinate traits in lines of house mice selectively bred for high voluntary wheel running

2006 ◽  
Vol 101 (2) ◽  
pp. 477-485 ◽  
Author(s):  
Enrico L. Rezende ◽  
Fernando R. Gomes ◽  
Jessica L. Malisch ◽  
Mark A. Chappell ◽  
Theodore Garland
Keyword(s):  
Muscle Mass ◽  
Citrate Synthase ◽  
Wheel Running ◽  
Maximal Oxygen Consumption ◽  
Hemoglobin Concentration ◽  
Cellular Respiration ◽  
Voluntary Wheel Running ◽  
Hindlimb Muscle ◽  
The Individual ◽  
Voluntary Wheel

We studied relations between maximal O2 consumption (V̇o2 max) during forced exercise and subordinate traits associated with blood O2 transport and cellular respiration in four lines of mice selectively bred for high voluntary wheel running (S lines) and their four nonselected control (C) lines. Previously, we reported V̇o2 max of 59 females at three Po2 (hypoxia = 14% O2, normoxia = 21%, hyperoxia = 30%). Here, we test the hypothesis that variation in V̇o2 max can be explained, in part, by hemoglobin concentration and Po2 necessary to obtain 50% O2 saturation of Hb (an estimate of Hb affinity for O2) of the blood as well as citrate synthase activity and myoglobin concentration of ventricles and gastrocnemius muscle. Statistical analyses controlled for body mass, compared S and C lines, and also considered effects of the mini-muscle phenotype (present only in S lines and resulting from a Mendelian recessive allele), which reduces hindlimb muscle mass while increasing muscle mass-specific aerobic capacity. Although S lines had higher V̇o2 max than C, subordinate traits showed no statistical differences when the presence of the mini-muscle phenotype was controlled. However, subordinate traits did account for some of the individual variation in V̇o2 max. Ventricle size was a positive predictor of V̇o2 max at all three Po2. Blood Hb concentration was a positive predictor of V̇o2 max in S lines but a negative predictor in C lines, indicating that the physiological underpinnings of V̇o2 max have been altered by selective breeding. Mice with the mini-muscle phenotype had enlarged ventricles, with higher mass-specific citrate synthase activity and myoglobin concentration, which may account for their higher V̇o2 max in hypoxia.

Permeability of Endometrial Blood Vessels to Exogenous Horse Radish Peroxidase in Mice. Electron Microscope Study

1973 ◽  
Vol 31 ◽  
pp. 562-563
Author(s):  
M.C. Castillo-Jessen ◽  
A. González-Angulo
Keyword(s):  
Electron Microscopy ◽  
Blood Vessels ◽  
Electron Microscope Study ◽  
Ultrastructural Level ◽  
Low Molecular Weight ◽  
Horse Radish Peroxidase ◽  
Intravascular Injection ◽  
Normal Morphology ◽  
Functional Implications ◽  
Low Molecular Weight Proteins

Information regarding the normal morphology of uterine blood vessels at ultrastructural level in mammals is scarce Electron microscopy studies dealing with endometrial vasculature despite the functional implications due to hormone priming are not available. Light microscopy observations with combined injection of dyes and microradiography along with histochemical studies does not enable us to know the detailed fine structure of the possible various types of blood vessels in this tissue. The present work has been designed to characterize the blood vessels of endometrium of mice as well as the behavior of the endothelium to injection of low molecular weight proteins during the normal estrous cycle in this animal. One hundred and forty female albino mice were sacrificed after intravascular injection of horse radish peroxidase (HRP) at 30 seconds, 5, 15, 30 and 60 minutes.

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