scholarly journals A Survey of Methionine Adenosyltransferase and Cystathionine "g-Lyase Activities in Ruminant Tissues

1974 ◽  
Vol 27 (5) ◽  
pp. 465 ◽  
Author(s):  
BC Radcliffe ◽  
AR Egan
Keyword(s):  
Skeletal Muscle ◽  
Methionine Adenosyltransferase ◽  
Kidney Cortex ◽  
Duodenal Wall ◽  
Kidney Medulla ◽  
Key Enzymes ◽  
Adult Sheep ◽  
Adult Rat

The activities of two key enzymes, methionine adenosyltransferase (EC 2.5.1.6) and cystathionine y-lyase (EC 4.4.1.1), involved in the metabolism of methionine to cyst(e)ine have been studied in the liver, heart, kidney medulla, kidney cortex, pancreas, duodenal wall, spleen and skeletal muscle in the neonatallarnb, unweaned lamb, adult sheep, pre-ruminant calf, ruminant steer and adult goat, and for comparative purposes in the adult rat.

scholarly journals Relationships between carnitine and coenzyme A esters in tissues of normal and alloxan-diabetic sheep

1972 ◽  
Vol 127 (1) ◽  
pp. 133-141 ◽  
Author(s):  
A. M. Snoswell ◽  
Patricia P. Koundakjian
Keyword(s):  
Skeletal Muscle ◽  
Alloxan Diabetes ◽  
Biceps Femoris ◽  
Kidney Cortex ◽  
Carnitine Acetyltransferase ◽  
Total Acid ◽  
Acetyl Coa ◽  
Adult Sheep ◽  
Ruminant Metabolism

1. The total acid-soluble carnitine concentrations of four tissues from Merino sheep showed a wide variation not reported for other species. The concentrations were 134, 538, 3510 and 12900nmol/g wet wt. for liver, kidney cortex, heart and skeletal muscle (M. biceps femoris) respectively. 2. The concentration of acetyl-CoA was approximately equal to the concentration of free CoA in all four tissues and the concentration of acid-soluble CoA (free CoA plus acetyl-CoA) decreased in the order liver>kidney cortex>heart>skeletal muscle. 3. The total amount of acid-soluble carnitine in skeletal muscle of lambs was 40% of that in the adult sheep, whereas the concentration of acid-soluble CoA was 2.5 times as much. A similar inverse relationship between carnitine and CoA concentrations was observed when different muscles in the adult sheep were compared. 4. Carnitine was confined to the cytosol in all four tissues examined, whereas CoA was equally distributed between the mitochondria and cytosol in liver, approx. 25% was present in the cytosol in kidney cortex and virtually none in this fraction in heart and skeletal muscle. 5. Carnitine acetyltransferase (EC 2.3.1.7) was confined to the mitochondria in all four tissues and at least 90% of the activity was latent. 6. Acetate thiokinase (EC 6.2.1.1) was predominantly (90%) present in the cytosol in liver, but less than 10% was present in this fraction in heart and skeletal muscle. 7. In alloxan-diabetes, the concentration of acetylcarnitine was increased in all four tissues examined, but the total acid-soluble carnitine concentration was increased sevenfold in the liver and twofold in kidney cortex. 8. The concentration of acetyl-CoA was approximately equal to that of free CoA in the four tissues of the alloxan diabetic sheep, but the concentration of acid-soluble CoA in liver increased approximately twofold in alloxan-diabetes. 9. The relationship between CoA and carnitine and the role of carnitine acetyltransferase in the various tissues is discussed. The quantitative importance of carnitine in ruminant metabolism is also emphasized.

The fate and uptake of murine epidermal growth factor in the sheep

1989 ◽  
Vol 123 (1) ◽  
pp. 121-130 ◽  
Author(s):  
L. M. Tyson ◽  
C. A. Browne ◽  
G. Jenkin ◽  
G. D. Thorburn
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Bolus Injection ◽  
Kidney Cortex ◽  
Kidney Medulla ◽  
Body Tissues ◽  
Rapid Fall ◽  
Epidermal Growth ◽  
Slow Rise ◽  
Initial Bolus

ABSTRACT 125I-Labelled murine epidermal growth factor (EGF) was injected or infused into conscious ewes through the jugular vein. Its disappearance from the circulation and the pattern of its distribution in other body tissues and compartments were observed. Single bolus injections of 125I-labelled EGF resulted in a transient peak of radioactive EGF in the circulation which occurred within 1 min of the injection. This was followed by a very rapid fall in radioactivity in the plasma (t½ ∼ 1 min) and the gradual appearance of 125I-labelled EGF in the urine. Immunoprecipitable 125I-labelled EGF could be detected in urine within 5 min of the start of the experiment. 125I-Labelled EGF accumulated in the urine for several hours following the injection, although with increasing time a substantial amount of non-immunoprecipitable iodide was also found. The rate of disappearance of the 125I-labelled EGF from the plasma of the ewe was found to be faster than the rate of disappearance of free [125I]iodide that had been injected into the ewe. 125I-Labelled EGF was also administered by a continuous infusion following an initial bolus injection. This again resulted in a rapid initial fall in radio-activity in blood, followed by a slow rise throughout the period of the infusion. When the infusion was stopped, there was a 15-min period of rapid readjustment, after which the radioactivity in the blood fell at a much slower rate (t½ ∼70 min) than was seen initially. Again, intact 125I-labelled EGF was transferred to urine throughout the experiment. At autopsy, 125I-labelled EGF was increased in bile, liver, thyroid and kidney. Although most of the 125I found in the thyroid was free iodide, some EGF-like material was also present. There was also EGF-like material found in both the kidney cortex and the kidney medulla. These results indicate that complex multi-compartment pathways for the uptake, distribution and clearance of 125I-labelled EGF exist in the sheep. Journal of Endocrinology (1989) 123, 121–130

Stable incorporation of a bacterial gene into adult rat skeletal muscle in vivo

1990 ◽  
Vol 258 (3) ◽  
pp. C578-C581 ◽  
Author(s):  
D. B. Thomason ◽  
F. W. Booth
Keyword(s):  
Skeletal Muscle ◽  
Leukemia Virus ◽  
Rat Skeletal Muscle ◽  
Bacterial Gene ◽  
Muscle Gene Expression ◽  
Adult Rat ◽  
Foreign Genes ◽  
Muscle Gene ◽  
Beta Galactosidase

We have developed a novel technique to incorporate and stably express foreign genes in adult rat skeletal muscle in vivo. Endogeneous satellite cells in skeletal muscle regenerating from bupivacaine damage were infected with an injected retrovirus containing the Escherichia coli beta-galactosidase gene under the promoter control of the Moloney murine leukemia virus long-terminal repeat. Constitutive and stable expression of beta-galactosidase activity was observed in muscle fibers after 6 days and 1 mo of muscle regeneration. Two patterns of expression were observed, diffuse expression within fibers and focal expression associated with the sarcolemma. This technique will allow future experiments with muscle-specific genes and promoters to study the physiological regulation of skeletal muscle gene expression in the intact adult mammal. Furthermore, the technique of stimulating stem cell proliferation to allow retroviral-mediated gene transfer may be generally applicable to other tissues.

Assessment of the Method and Timing of Repair of a Brachial Plexus Traction Injury in an Animal Model for Obstetric Brachial Plexus Palsy

2002 ◽  
Vol 27 (1) ◽  
pp. 13-19 ◽  
Author(s):  
A. C. FULLARTON ◽  
D. V. LENIHAN ◽  
L. M. MYLES ◽  
M. A. GLASBY
Keyword(s):  
Skeletal Muscle ◽  
Brachial Plexus ◽  
Brachial Plexus Palsy ◽  
Nerve Fibres ◽  
Obstetric Brachial Plexus Palsy ◽  
Adult Sheep ◽  
Type Iv ◽  
Traction Injury ◽  
Obstetric Brachial Plexus ◽  
Injury And Repair

A Sunderland type IV traction injury to the C6 root of adult sheep or newborn lamb brachial plexus was used as a model for obstetric traction injury to the C5 root in humans. In one experimental cohort the injury was created and repaired using interfascicular nerve autografts or coaxially aligned freeze-thawed skeletal muscle autografts in a group of adult sheep and in a group of newborn lambs. In a second cohort a similar injury was created and repaired either immediately or after a delay of 30 days, using either interfascicular nerve autografts or coaxially aligned freeze-thawed skeletal muscle autografts in four groups of six newborn lambs. In all cases both functional and morphometric indices of nerve regeneration were poorer in the injured and repaired nerves than in normal nerves. In lambs the method of repair made no difference and no significant differences were found for any of the indices of nerve function or morphology. In sheep the use of muscle grafts was associated with a poorer outcome than the use of nerve autografts. Where a delay of 30 days had elapsed between injury and repair, the results using nerve autografts were not significantly different. Where freeze-thawed muscle autografts had been used, the maturation of the regenerated nerve fibres after delay was significantly poorer than after immediate repair. The electrophysiological variables CVmax and jitter, which may be applied clinically, were found to be good discriminators of recovery in all of the animals and in respect of all procedures.

scholarly journals Comparison of the kinetic properties of the pyruvate dehydrogenase complex from pig kidney cortex and medulla.

1993 ◽  
Vol 40 (3) ◽  
pp. 411-419 ◽  
Author(s):  
T Pawełczyk ◽  
M S Olson
Keyword(s):  
Ionic Strength ◽  
Pyruvate Dehydrogenase ◽  
Pyruvate Dehydrogenase Complex ◽  
Product Inhibition ◽  
Hill Coefficient ◽  
Kidney Cortex ◽  
Kinetic Properties ◽  
Kidney Medulla ◽  
Pig Kidney ◽  
Dehydrogenase Complex

The activity of the pyruvate dehydrogenase complex (PDC) purified from pig kidney medulla was affected by K+, Na+, Cl-, HCO3-, HPO4(2-) and changes in ionic strength. Increased ionic strength influenced the activity of PDC from medulla by decreasing the Vmax and S0.5 for pyruvate and increasing the Hill coefficient. The magnitude of these changes was smaller than the corresponding changes for PDC purified from the cortex. In the presence of K+ (80 mM), Na+ (20 mM), Cl- (20 mM), HCO3- (20 mM), HPO4(2-) (10 mM) and at ionic strength of 0.15 M the S0.5 for pyruvate of PDC from medulla was 117 microM and the enzyme complex was saturated by 1.1 mM pyruvate. Under these conditions the S0.5 for pyruvate of PDC derived from cortex was 159 microM and the enzyme was saturated at 4.5 mM pyruvate. Based on the results presented in this report it is suggested that PDC in kidney medulla may be regulated not only by a phosphorylation/dephosphorylation system and end-product inhibition but also via changes in ionic strength.

scholarly journals Detecting metabolic differences in fetal and adult sheep adipose and skeletal muscle tissues

2019 ◽  
Vol 13 (3) ◽  
Author(s):  
Jack R. T. Darby ◽  
Alexandra Sorvina ◽  
Christie A. Bader ◽  
Mitchell C. Lock ◽  
Jia Yin Soo ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Adult Sheep ◽  
Muscle Tissues

scholarly journals Basic biochemical characterization of cytosolic enzymes in thymidine nucleotide synthesis in adult rat tissues: implications for tissue specific mitochondrial DNA depletion and deoxynucleoside-based therapy for TK2-deficiency

2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Liya Wang ◽  
Ren Sun ◽  
Staffan Eriksson
Keyword(s):  
Skeletal Muscle ◽  
Mitochondrial Dna ◽  
Biochemical Characterization ◽  
Basic Knowledge ◽  
Rat Tissues ◽  
Nucleotide Synthesis ◽  
Tissue Specific ◽  
Mtdna Depletion ◽  
Adult Rat ◽  
Mitochondrial Dna Depletion

Abstract Background Deficiency in thymidine kinase 2 (TK2) or p53 inducible ribonucleotide reductase small subunit (p53R2) is associated with tissue specific mitochondrial DNA (mtDNA) depletion. To understand the mechanisms of the tissue specific mtDNA depletion we systematically studied key enzymes in dTMP synthesis in mitochondrial and cytosolic extracts prepared from adult rat tissues. Results In addition to mitochondrial TK2 a cytosolic isoform of TK2 was characterized, which showed similar substrate specificity to the mitochondrial TK2. Total TK activity was highest in spleen and lowest in skeletal muscle. Thymidylate synthase (TS) was detected in cytosols and its activity was high in spleen but low in other tissues. TS protein levels were high in heart, brain and skeletal muscle, which deviated from TS activity levels. The p53R2 proteins were at similar levels in all tissues except liver where it was ~ 6-fold lower. Our results strongly indicate that mitochondria in most tissues are capable of producing enough dTTP for mtDNA replication via mitochondrial TK2, but skeletal muscle mitochondria do not and are most likely dependent on both the salvage and de novo synthesis pathways. Conclusion These results provide important information concerning mechanisms for the tissue dependent variation of dTTP synthesis and explained why deficiency in TK2 or p53R2 leads to skeletal muscle dysfunctions. Furthermore, the presence of a putative cytosolic TK2-like enzyme may provide basic knowledge for the understanding of deoxynucleoside-based therapy for mitochondrial disorders.

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