OBJECTIVETo study the characteristics of changes of LDH enzyme patterns of mice under slight hypoxia.

METHODSMice treated with artificial hypoxia, various tissues were made for the test of LDH enzymatic activity by the specific staining technique. LDH (1-5) relative percentage enzymatic activity (RPEA) were measured with CS-910 dual-wavelength thin layer chromatography scanner.

RESULTSThe RPEA of LDH isozymes of various tissues after slight hypoxia shifted to the isozymes LDH1 and LDH2, whose principal subunits are H subunits, and the RPEA of LDH1 (H4), LDH2 (H3M) increased, while RPEA of LDH5 (M4) in various tissues decreased prominently except the cardiac muscle, and that of LDH4 (HM3) decreased as well. After polyacrylamide gel electrophoresis (PAGE) of the hypoxia treated cardiac muscle specimen was made, activity subbands originated regularly in the isoyme patterns of LDH, with the regularity of LDH1 (0 subband), LDH2 (0-1 subbands), LDH3 (0-2 subbands), LDH4 (1-3 subbands), LDH5 (2-4 subbands). After adding appropriate amount of NAD+ to the hypoxia treated cardiac muscle specimen, PAGE showed the subbands of four isoymes (LDH2-LDH5) reduced or even totally disappeared in the isozyme patterns.

CONCLUSIONSThe negative feedback regulation of coenzymization and decoenzymization of LDH isozymes is one of the mouse stress responses to slight hypoxia.

Animals ; Hindlimb ; enzymology ; Hypoxia ; enzymology ; Isoenzymes ; metabolism ; L-Lactate Dehydrogenase ; classification ; metabolism ; Liver ; enzymology ; Mice ; Muscles ; enzymology ; Myocardium ; enzymology ; Random Allocation

OBJECTIVETo study the effects of inducible NOS inhibitor aminoguanidine on the expression of NOS in facial nerve and surrounding tissue of traumatic facial paralysis rats.

METHODSA small dose of aminoguanidine were intraperitoneally injected into rats before and after facial paralysis. The facial nerve and surrounding tissues were cut at different time point. Immunohistochemical ABC method was used to study the changes of NOS expression in facial nerve and surrounding tissues.

RESULTSThe inducible NOS immunoreactivity was obvious inhibited in the facial nerve and surrounding tissues in aminoguanidine group.

CONCLUSIONAminoguanidine chronic treatment can obvious inhibit the inducible NOS expression in the facial nerve and surrounding tissues. Aminoguanidine can improve the regeneration of facial nerve and the recovery of traumatic tissues.

Animals ; Facial Nerve ; enzymology ; Facial Nerve Injuries ; enzymology ; Facial Paralysis ; enzymology ; Guanidines ; pharmacology ; Male ; Muscles ; enzymology ; Nerve Regeneration ; Nitric Oxide Synthase ; antagonists & inhibitors ; metabolism ; Nitric Oxide Synthase Type II ; Random Allocation ; Rats ; Rats, Sprague-Dawley

The purpose of this study were 1) to determine the earliest pathological changes of germanium dioxide (GeO2)-induced myopathy; 2) to determine the pathomechanism of GeO2-induced myopathy; and 3) to determine the minimal dose of GeO2 to induce myopathy in rats. One hundred and twenty five male and female Sprague-Dawley rats, each weighing about 150 gm, were divided into seven groups according to daily doses of GeO2. Within each group, histopathological studies were done at 4, 8, 16, and 24 weeks of GeO2 administration. Characteristic mitochondrial myopathy was induced in the groups treated daily with 10 mg/kg of GeO2 or more. In conclusion, the results were as follows: 1) The earliest pathological change on electron microscope was the abnormalities of mitochondrial shape, size and increased number of mitochondria; 2) The earliest pathological change on light microscope was the presence of ragged red fibers which showed enhanced subsarcolemmal succinate dehydrogenase and cytochrome c oxidase reactivity; 3) GeO2 seemed to affect the mitochondrial oxidative metabolism of muscle fibers; 4) GeO2 could induce mitochondrial myopathy with 10 mg/kg of GeO2 for 4 weeks or less duration in rats.
Animal ; Cytochrome-c Oxidase/metabolism ; Female ; Germanium/toxicity* ; Histocytochemistry ; Male ; Mitochondrial Myopathies/pathology ; Mitochondrial Myopathies/enzymology ; Mitochondrial Myopathies/chemically induced* ; Muscles/ultrastructure ; Muscles/enzymology ; Rats ; Rats, Sprague-Dawley ; Succinate Dehydrogenase/metabolism

The study was conducted to investigate fasting effects on flesh composition and antioxidant defenses of market-size Sparus macrocephalus. Two hundred fish (main initial weight 580 g) were divided into two groups (control and fasted) and reared in 6 cages. After two weeks of adaptation, group I fasted for 28 d; group II was fed normally as a control. In 3, 7, 14, 21 and 28 d, 6 fish per group were sampled for proximate flesh composition, liver antioxidant enzyme activities and malondialdehyde flesh content analyses. In fasted fish, the reduction of lipid content in muscle occurred after day 3, and, compared to controls, the content of protein decreased from day 14, the activities of liver antioxidative enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPX) increased from day 3, and flesh malondialdehyde levels increased from day 21. Flesh fat reduction shows that fasting may be used as a technique to reduce flesh lipid content in Sparus macrocephalus. However, considering flesh protein loss and the subsequent oxidative stress, the fasting technique should be used with precautions.
Animal Feed ; Animals ; Antioxidants ; metabolism ; Fasting ; physiology ; Glutathione Peroxidase ; metabolism ; Liver ; enzymology ; Malondialdehyde ; metabolism ; Muscles ; metabolism ; Perciformes ; metabolism ; Superoxide Dismutase ; metabolism

OBJECTIVEThe purpose of this study was to study the masticatory muscles affected by distraction osteogenesis of the mandible.

METHODSThe distraction osteogenesis (DO) was applied to distract the left mandible of 6 mongrel dogs that were divided into three experimental groups. After different distraction phase and consolidation phase, the masseter and the digastric muscle were taken out. The specimens were stained using hematoxylin/eosin and enzyme histochemistry. Afterwards, the specimens were observed with a light microscope to study the morphologic changes of the muscles. The contents of enzyme in the different groups were measured by VIDAS.

RESULTSThe masseter showed consequently atrophy, but the digastric muscle showed a progress of histomorphologic reconstruction, including atrophy and hypertrophy. The changes of the contents of enzyme and histomorphology were identical in the masticatory muscles.

CONCLUSIONThe digastric muscle parallel to the vector of mandibular distraction adapts the distraction by the way of atrophy, regeneration and hypertrophy. And the contents of enzyme appear to decrease at the beginning, increase afterwards, and return to the normal level finally. But the masseter perpendicular to the vector of mandibular distraction shows consequent atrophy, and the contents of enzyme consequently decrease, which means the metabolism decrease.

Adenosine Triphosphatases ; analysis ; Animals ; Dogs ; Female ; L-Lactate Dehydrogenase ; analysis ; Male ; Mandible ; surgery ; Masticatory Muscles ; anatomy & histology ; enzymology ; Osteogenesis, Distraction ; Random Allocation

OBJECTIVEGlycogen storage disease type III (GSD III) is an autosomal recessive disease caused by glycogen debranching enzyme (GDE) gene (AGL gene) mutation resulting in hepatomegaly, hypoglycemia, short stature and hyperlipidemia. GSD IIIA, involves both liver and muscle, and accounts for up to 80% of GSD III. The definitive diagnosis depends on either mutation analysis or liver and muscle glycogen debranching enzyme activity tests. This study aimed to establish enzymologic diagnostic method for GSD IIIA firstly in China by detecting muscular GDE activity, glycogen content and structure and to determine the normal range of muscular GDE activity, glycogen content and structure in Chinese children.

METHODMuscle samples were collected from normal controls (male 15, female 20; 12-78 years old), molecularly confirmed GSD III A patients (male 8, female 4, 2-27 years old) and other myopathy patients (male 9, 2-19 years old). Glycogen in the muscle homogenate was degraded into glucose by amyloglucosidase and phosphorylase respectively. The glycogen content and structure were identified by glucose yield determination. The debranching enzyme activity was determined using limit dextrin as substrate. Independent samples Kruskal-Wallis H test, Nemenyi-Wilcoxson-Wilcox test, and Chi-square test were used for statistical analyses by SPSS 11.5.

RESULT(1) GSD III A patients' glycogen content were higher, but G1P/G ratio and GDE activity were lower than those of the other two groups (P < 0.01). In all of the three parameters, there were no significant difference between normal controls and other myopathy patients. (2) The range of normal values: glycogen content 0.31%-0.43%, G1P/G ratio 22.37%- 26.43%, GDE activity 0.234-0.284 micromol/(g. min). (3) Enzymologic diagnostic method had a power similar to that of gene analysis in diagnosis of GSD-IIIA patients. The sensitivity and specificity of enzymologic diagnostic method and mutation detection were 91.7% and 100% respectively.

CONCLUSIONEnzymologic diagnostic method of GSD IIIA was firstly established in China. The range of normal values was determined. This method could be used in diagnosing suspected GSD IIIA patients in the clinic.

Adolescent ; Adult ; Aged ; Biopsy ; Case-Control Studies ; Child ; Child, Preschool ; China ; Female ; Glycogen ; analysis ; Glycogen Debranching Enzyme System ; analysis ; Glycogen Storage Disease Type III ; diagnosis ; enzymology ; pathology ; Humans ; Male ; Middle Aged ; Muscles ; chemistry ; pathology ; Young Adult

The persistence of muscle fiber number regardless of size reduction in muscle atrophy has not yet been fully explained. For the mechanism inherent in skeletal muscle tissues for preventing cellular death, the protective function of muscle tissue through transglutaminases has been tested, since the enzyme is responsible for structural stabilization and participates in signal transduction. In the present experiment, hindlimb suspension for two weeks caused a marked muscle atrophy in Wistar female rats. Comparison of muscle weight and histological analysis showed that suspension-induced atrophy in the hindlimb was more prominent in the soleus muscle, comprised mainly of type I fiber than that in the plantaris muscle of type II fibers. The immunohistochemical analysis with antitransglutaminase C antibody (anti TGase C Ab) showed that some atrophic bundles of soleus muscle were positively reacted with the antibody. The anti-TGase C Ab-reactive substances were observed to disappear significantly after endurance exercise, indicating their characteristic atrophy-dependency. The enzymatic analysis of transglutaminase showed the increase in activity in the atrophic soleus muscle tissue, compared with that in the normal or exercise-trained muscle tissues. From these results, the expression of TGase in the atrophic muscle is suggested to be the possible marker for muscle atrophy and its expression is probably related with the protective mechanism of the muscle tissue to prevent further cellular damage in the atrophic process.
Animal ; Atrophy ; Comparative Study ; Enzyme Induction ; Female ; Hindlimb ; Immobilization ; Muscle Fibers/pathology ; Muscle Proteins/*biosynthesis ; Muscles/*enzymology/pathology ; Physical Conditioning, Animal ; *Physical Endurance ; Rats ; Rats, Wistar ; Support, Non-U.S. Gov't ; Swimming ; Transglutaminases/*biosynthesis

OBJECTIVETo investigate the role of c-Jun NH (2)-terminal kinase (JNk) in insulin resistance after burn and its mechanism.

METHODSTwenty-four Sprague-Dawley rats were randomized to control, burn and burn + anisomycin groups. The rats in control group received sham burn trauma, and burn and burn + anisomycin groups received 30% total body surface area (TBSA) full thickness burn injury. Anisomycin (5 mg/kg) together with 250 microl dimethyl sulfoxide (DMSO) was injected to the rats in anisomycin group intravenously, and only 250 microl DMSO in the other two groups. Euglycemic-hyperinsulinemic glucose clamps was performed 2 hours after the injection. The changes of phospho-serine 307, phospho-tyrosine of insulin receptor substrate (IRS)-1 and phospho-JNK in muscle tissues were determined and compared using immunoprecipitation and Western blot analysis or immunohistochemistry in the three groups.

RESULTSThe infusing rates of total 10% glucose (mg x kg(-1) x min(-1)) in control, burn and burn + anisomycin group were 12.3 +/- 0.4, 6.6 +/- 0.3, 6.5 +/- 0.4, respectively. The level of IRS-1 Serine 307 phosphorylation and phospho-JNK in muscle increased significantly, while insulin-induced tyrosine phosphorylation of IRS-1 decreased markedly after burn.

CONCLUSIONSThe activation of JNK elevates the level of IRS-1 phospho-serine 307 and might play a role in insulin resistance after burn in rats.

Adaptor Proteins, Signal Transducing ; metabolism ; Animals ; Anisomycin ; administration & dosage ; Anti-Bacterial Agents ; administration & dosage ; Blotting, Western ; Burns ; enzymology ; metabolism ; physiopathology ; Dimethyl Sulfoxide ; administration & dosage ; Disease Models, Animal ; Female ; Glucose Clamp Technique ; Immunohistochemistry ; Injections, Intravenous ; Insulin ; administration & dosage ; Insulin Receptor Substrate Proteins ; Insulin Resistance ; physiology ; JNK Mitogen-Activated Protein Kinases ; metabolism ; Male ; Muscles ; metabolism ; Phosphorylation ; drug effects ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Serine ; metabolism ; Tyrosine ; metabolism