Lactate dehydrogenase isozymes of mouse epidermis

Summary Five isozymes of LDH are demonstrable in the epidermis of the ear pinnae, hind feet, trunk dorsa, and tails of adult C57BL, C57HR, and C3HB mice by polyacrylamide gel electrophoresis. LDH-5 activity predominates in electropherograms. The ratio of LDH-1 to LDH-5 is greater in the epidermis of ear pinna and trunk dorsum than in that of tail and hind foot. The region-specific patterns of epidermal LDH isozymes are not correlated with melanin pigmentation or ‘hairiness’ of the skin. Supported by PHS Research Grant No. CA-06097 from the National Cancer Institute, United States Public Health Service.     

Variation in the lactase dehydrogenase activity of the esophagus

Quantitative assay and electrophoretic study of lactate dehydrogenase (LDH) from various tissues of the opossum esophagus were performed. On the basis of expression of the LDH isozymes, we concluded that the smooth muscle of the body of the esophagus carry on more anaerobic glycolysis than the striated muscle. The smooth muscle of the gastroesophageal junction carry on both anaerobic as well aerobic glycolysis.     

Mitosenverteilung in der larvalen Rumpfepidermis vonSalamandra maculosa Laur.

Summary In the larval epidermal trunk region ofSalamandra maculosa, the total number of mitoses of both sides is approximately the same. This applies to the differentiated Leydig cells as well as to the rest of the epidermis cells.With respect to the meristic segmentation of the trunk, we find within the single segments a regular rise of the mitotic rate, which alternates from one side to the other.From the total number of mitoses found in the epidermis of the trunk, approximately 40% can be accounted for to the dorsal and 60% to the ventral region of the trunk. The number of cells is the same for both the ventral and dorsal region.     

A testis-specific lactate dehydrogenase in the pipid frog,Hymenochirus boettgeri

Summary Lactate dehydrogenase zymograms of mature testes ofHymenochirus boettgeri show in addition to the five isozymes composed of LDH-A and LDH-B subunits, a second 5-band system which is due to isozymes formed between LDH-A and a third subunit, LDH-C. These testis-specific LDH-C isozymes appear around 6 months after metamorphosis indicating that their expression is correlated with sexual maturity as is generally the case in mammals. This is the first report of a testis-specific LDH isozyme in a lower tetrapod; such isozymes have hitherto only been reported in mammals and in the pigeon.This study was supported by a grant from the Fond National Suisse de la Recherche Scientifique to H.R.K. We thank M. Sateur and F. Bourquin for their technical help.     

Genetic control of LDH isozymes in the Rana esculenta complex.

Studies of LDH isozymes in the European green frogs showed that the synthesis of the B subunits is controlled by 3 alleles at a single genetic locus. The genetic evidence supports the hypothesis that Rana esculenta is the hybrid of R. lessonae X R. ridibunda.     

Variation in the lactase dehydrogenase activity of the esophagus

Summary Quantitative assay and electrophroetic study of lactate dehydrogenase (LDH) from various tissues of the opossum esophagus were performed. On the basis of expression of the LDH isozymes, we concluded that the smooth muscle of the body of the esophagus carry on more anaerobic glycolysis than the striated muscle. The smooth muscle of the gastroesophageal junction carry on both anaerobic as well aerobic glycolysis.Acknowledgments. This work was supported by Kelsey-Leary Foundation grant No. 962, Houston, Texas. We appreciate the technical assistance of Henry D. Kasten, and Carol K. Kitson.     

Rapid purification of lactate dehydrogenase X from mouse testes by two steps of affinity chromatography on oxamate-sepharose.

At concentrations of 200 muM NADH and 0.5 M NaCl LDH-X is separated from the other LDH isozymes of mouse testes on oxamate-sepharose. In a second step LDH-X is bound to the same matrix at lower NADH and NaCl concentrations and the pure enzyme can subsequently be eluted.     

The time course of plasma enzyme changes accompanying skeletal muscle stimulation

Summary 30 min electrical stimulation of hind limb skeletal muscle in nembutal anaesthetised dogs was accompanied by increases in arterial haematocrit, plasma GOT and plasma LDH, which were almost completed within the first 10 min of stimulation. This fast response indicated that a rapid change in either the entry and/or clearance of enzyme from the plasma must have occurred.     

Genetic control of LDH isozymes in theRana esculenta complex

Summary Studies of LDH isozymes in the European green frogs showed that the synthesis of the B subunits is controlled by 3 alleles at a single genetic locus. The genetic evidence supports the hypothesis thatRana esculenta is the hybrid ofR. lessonae x R. ridibunda.This work was supported by grants from the Schweizerischer Nationalfonds, the Georges und Antoine Claraz-Schenkung and the Karl Hescheler-Stiftung.     

A further study of LDH isozymes in theRana esculenta complex

Summary Electrophoretic analyses of LDH isozymes in the 3 types of European green frogs by using the buffer system of Williams and Reisfeld demonstrated the occurrence of 4 allelic genes coding for the B subunits. Based on the distribution of these alleles and results from dissociation and recombination of the subunits, the hybrid nature of Rana esculenta is confirmed.This study was supported in part by the Swiss National Science Foundation and the Georges-und-Antoine-Claraz-Schenkung.     

Dystrophic mutation (dy2J) affecting regulation of lactate dehydrogenase (LDH) and pyruvate kinase (PK) in C57BL/6J mice

Summary The genotype difference (dystrophic vs nondystrophic) in the LDH isozymes is observed in kidney. These differences are evident only at birth and at early developmental stages (before the expression of dystrophic symptoms). The tissue specific genotype differences for PK are limited to the thigh muscle (M form) and heart (L form), after the onset of the condition. These differences may reflect the pleiotropic effect of the dy^2J locus during the temporal regulation of these and other enzymes implicated in muscular dystrophy (MD).This research was financed by a Natural Sciences and Engineering Research Council Canada grant to S.M.S.     

Morphological and enzymehistochemical changes in the interscapular adipose tissue of adult guinea-pigs during prolonged exposure to cold

Zusammenfassung Dauereinwirkung von Kälte (2 Monate +4°C) führte beim Meerschweinchen zum Auftreten multilokularer Fettzellen, welche intensive histochemische Reaktion für mehrere oxydative Enzyme zeigten. Die Zahl der Mitochondrien und LDH-1 war im Kälteversuch vermehrt.

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Acknowledgment. This study was initiated when Dr.J. Hirvonen worked as a post-doctoral fellow of NIH, U.S. Public Health Service (No. F05 TW 1546) at Arctic Health Research Center, Fairbanks (Alaska).     

The chromosomal location of phosphatase isozymes of the wheat endosperm

Summary The 7 phosphatase isozymes found in the endosperm of hexaploid wheat (Triticum aestivum L.) are related to chromosomes of homoeology group 4. At least 4 loci are related to phosphatase isozymes.Acknowledgments: The authors thank Dr B. Cifuentes, P. González and E. Wiltshire for technical assistance.     

Rapid purification of lactate dehydrogenase X from mouse testes by two steps of affinity chromatography on oxamate-sepharose

Summary At concentrations of 200 M NADH and 0.5M NaCl LDH-X is separated from the other LDH isozymes of mouse testes on oxamate-sepharose. In a second step LDH-X is bound to the same matrix at lower NADH and NaCl concentrations and the pure enzyme can subsequently be eluted.Acknowledgment. This work was supported by grants of the Deutsche Forschungsgemeinschaft awarded to the Sonderforschungsbereich 29 Embryonale Differenzierung und Entwicklung.     

Alkaline phosphatase isozymes in cultured human cancer cells

Alkaline phosphatase, an ubiquitous enzyme is known to exist in several isozymic forms. At least three different isozymes have now been identified in humans. Alkaline phosphatase isozymes are among the substances synthesized ectopically by a variety of human tumors and many continuous cell lines derived from different cancers have retained the capacity to produce these membrane-located glycoproteins. This paper reviews the identification of alkaline phosphatase isozymes in cultured tumor cells and relates these findings with recent developments concerning these cell membrane located glycoproteins.     

Alkaline phosphatase isozymes in cultured human cancer cells

Summary Alkaline phosphatase, an ubiquitous enzyme is known to exist in several isozymic forms. At least three different isozymes have now been identified in humans. Alkaline phosphatase isozymes are among the substances synthesized ectopically by a variety of human tumors and many continuous cell lines derived from different cancers have retained the capacity to produce these membrane-located glycoproteins. This paper reviews the identification of alkaline phosphatase isozymes in cultured tumor cells and relates these finding with recent developments concerning these cell membrane located glycoproteins.     

Continued in vitro and in vivo release of an antitumor drug from albumin microspheres

Heated albumin microspheres with an average diameter of 45 +/- 8 microns and containing mitomycin C, released, in vitro, about 20% of this antibiotic over a 3-day period. VX-2 tumors were implanted into the hind leg of rabbits and the drug-containing microspheres were injected into the femoral artery of these animals. High levels of the drug were maintained for several hours in the tumor and growth of the tumor was inhibited considerably, compared to findings in control rabbits given the conventional mitomycin C. Half the number of the rabbits treated with our new method are alive with no evidence of tumor.     

Different action of alpha-methyl-DOPA on sleep and labyrinth learning in 2 inbred strains of mice]

In two inbred mice strains C 57 BR and C 57 BL/6 presenting the same type of sleep, but a different capacity of learning, Alpha-Methyl-Dopa (100 mg/kg) injected after every session, suppresses paradoxical sleep completely for 9 to 11 h. Maze-learning performance is retarded in C 57 BR mice, but facilitated in C 57 BL/6.     

Whole brain methionine-enkephalin of ethanol-avoiding and ethanol-preferring C57BL mice

Summary These experiments systematically investigated ethanol preference in both the C57Bl/6N and C57Bl/6J mice utilizing three-choice 2-bottle preference test. In addition, these sublines were evaluated for whole brain methionineenkephalin levels, which were significantly lower in C57Bl/6J mice (alcohol preferring) compared to C57Bl/6N mice (alcohol non-preferring). This finding supports the involvement of the peptidyl opiates in ethanol seeking behavior.     

Murine arylsulfatase C: Evidence for two isozymes

Summary SWR/J mice posses high arylsulfatase C, estrone sulfatase, and dehydroepiandrosterone sulfatase activities in liver, spleen and kidney compared to A/J mice. This internstrain activity variation appears to be determined by at least 1 autosomal gene. Murine arylsulfatase C activity occurs in both hydrophobic and hydrophilic forms which differ with respect to certain biochemical properties and exhibit different subcellular distributions. The hydrophilic isozyme is a major component in kidney and brain extracts and a minor isozyme in liver and spleen extracts. The hydrophobic arylsulfatase C isozyme appears to be identical to steroid sulfatase. The hydrophilic arylsulfatase C isozyme does not possess steroid sulfatase activity; however, hydrophilic and hydrophobic arylsulfatase C share certain properties, suggesting that they may be structurally related. The autosomal gene(s) affects both arylsulfatase isozymes.This research was supported in part by National Institutes of Health grant GM 27707.