Lactate Dehydrogenase Isozyme Patterns Research Articles

Comparative Electrophoretic Patterns of Lactate Dehydrogenase in Three Species of Trout

The isozyme patterns of lactate dehydrogenase (LDH) were examined in three species of trout using electrophoresis in polyacrylamide gel slabs. Each pattern was species specific and contained 15 isozymes of LDH, but a hybrid trout had at least 27 LDH isozymes. Tissue specificity of these isozymes was low except for skeletal muscle. These results suggest that LDH isozyme patterns could be used for taxonomic and diagnostic purposes.

Studies on the Lactic Dehydrogenase (LDH) during Development

SummaryThe serum LDH activity and the isozyme patterns in cord blood and the healthy individuals in different age were investigated during the development and the following results were obtained.1) LDH activityThe mean values in each group were as follows: 490.30 u/ml in cord blood, 623.60 u/ml in early newborns (1–3 days), 575.45 u/ml in newborns (4–7 days), 395.00 u/ml in infants (1–6 m), 371.00 u/ml in infants (6–12 m), 342.00 u/ml in young children (1–6 y), 298.24 u/ml in school children (6–15 y) and 212.00 u/ml in adults.Marked elevations of the activity were proved in the newborn group, especially 1–3 days after birth.After the newborn period, the activity gradually decreased to the adult level.No significant differences were obtained between the male and the female in each group.2) LDH isozymeThe distribution dominance of the LDH isozymes in all groups were indicated in the following order: LDH‐2>LDH‐1>LDH‐3>LDH‐4>LDH‐5.The LDH isozyme pattern in cord blood showed the specific pattern considerably different from those in other groups.The LDH isozyme patterns in newborn serum showed the statistically significant increase of LDH‐3, LDH‐4 and LDH‐5 as compared with those in other age groups and the alteration was marked in the early period of the newborn, 1–3 days after birth.3) The possible mechanisms of the changes of the serum LDH activity and the alterations of the isozyme patterns were discussed.

Effects of N-nitroso-N-methylurea on enzymatic ontogeny associated with teratogenesis.

AbstractThe teratogenic effects of N‐nitroso‐N‐methylurea on the rat embryo were investigated. Skeletal malformations were produced in rat embryos by a dose of 20 mg/kg of maternal body weight on day 13 of pregnancy. The structurally malformed fetuses had multiple malformations including: clubfeet, syndactyly, cleft palate, micrognathia, crooked tail, and hydrocephalus. Drug administered on day 8 or 10 at dosages of 5–20 mg/kg gave no malformations at term but tended to increase fetal mortality. A dose of 20 mg/kg on day 13, however, resulted in a high incidence of congenital malformations but did not increase the resorption rate. To correlate the structural malformations with biochemical changes, zone electrophoretic separation of several enzyme systems was carried out in starch and polyacrylamide gels. Variations from the normal isozyme patterns of lactate dehydrogenase, glucose‐6‐phosphate dehydrogenase, and nonspecific esterases were found in abnormally developing embryos and organs.

Lactate Dehydrogenase Isozyme Patterns in Blister Fluids

Lactate Dehydrogenase Isozyme Patterns in Blister Fluids

Differences in isozyme patterns of nucleic and cytoplasmic lactate dehydrogenase of rat liver cells.

THE resistance of lactate dehydrogenase (LDH) activity to the denaturating action of 4 molar urea in the nuclei of rat liver cells is considerably greater than that in the cytoplasm1. To investigate these differences we have examined the resistance of LDH to high temperatures and the relationship of temperature to substrate (pyruvate) concentration. We have also determined LDH isozymes in starch gel after electrophoresis.

Studies on lactic dehydrogenase of cancer cells and host tissues before and after tumor inoculation.

Plasma lactate in tumor-bearing rats increased progressively after inoculation with tumor cells. Plasma lactic dehydrogenase (LDH) activities were found increased in tumor-bearing rats, especially in cases of liver metastasis. The similarity between the LDH isozyme patterns of the plasma in tumor-bearing rats and those of the ascites tumor cells suggested that the tumor cells contributed greatly to the increase in plasma LDH of these animals. Michaelis constants for pyruvate of rat tissues and ascites tumor cells were closely related to the iso-zyme patterns.

Studies on kidney tubulogenesis: X. The effect of actinomycin D on the development of the lactate dehydrogenase isozyme pattern during tubule formation in vitro

The effect of actinomycin D on tubule formation and on the change in lactate dehydrogenase ( l-lactate: NAD + oxidoreductase, EC I.I.I. 27) (LDH) isozyme pattern during the differentiation of mouse metanephrogenic mesenchyme in organotypic culture was studied. LDH isozyme composition was known to display a radical shift from the cathodal end of the spectrum of five isozymes almost to the anodal end during six days' development of kidney mesenchyme in vitro. Subsequent tubule formation and the shift in LDH pattern were prevented when the mesenchyme-spinal cord explant was exposed to actinomycin during the first 24 hr of transfilter contact in vitro. Exposure to actinomycin at 28–30 hr after recombination no longer inhibited tubule morphogenesis, however, the LDH isozyme pattern displayed no shift in 7 out of 12 cases. A similar exposure at 32–35 hr of transfilter contact no longer had an inhibiting effect on overt morphogenesis or the LDH isozyme change. Radioautography with tritiated actinomycin and determination of total actinomycin incorporation showed that the differentiating cells do actually incorporate actinomycin. Hence it is concluded that the change in sensitivity of the differentiation markers studied does not reflect a decreased penetration of actinomycin into the cells. The significance of the differences in the sensitive periods of the two developmental events studied is discussed, as well as the role of genetic and epigenetic factors in chemo-differentiation.

Histochemical and electrophoretic studies of esterase in the regenerating forelimb of the adult newt, Triturus pyrrhogaster.

Histochemical and electrophoretic studies of esterase in the regenerating forelimb of the adult newt, Triturus pyrrhogaster.

Thermal stability of lactic dehydrogenase from human tissues.

Lactic dehydrogenase (LDH) is present in human and other mammalian tissues in the form of five distinct isoenzymes or isozymes. According to the subunits they contain, the five isozymes of LDH may be designated as H„, HjMi, H2M2, HxMa, and M4. 2 The H4 variety is characteristic of heart muscle and red cells, whereas liver and skeletal muscle are rich in the M4 form. Other tissues exhibiting LDH activity contain two or more isozymes in different and possibly distinctive combinations. These isozymes are soluble, and leak into the blood stream when tissue cell membranes are damaged. Thus the LDH isozyme pattern of serum may be studied to identify the tissue source as an aid in diagnosis. The isozymes of LDH may be detected by electrophoresis and by chromatography. They are immunologically distinct. They are affected differently by certain chemical inhibitors, specifically sulfite, oxalate, and urea. Their activities respond differently to changes of pH and temperature • 6 as well as to different substrates or different concentrations of the same substrate. They exhibit a considerable variation in their ability to survive incubation at high temperatures. Thermal stability and substrate specificity are the simplest of these properties to test for. Thermal stability affords a clearer differentiation between the H4 and M4 forms than does substrate specificity and would seem to be the method of choice. I t has proved useful in the differential diagnosis of myocardial or hepatic injury,' 8 where heat-stable LDH is consistently elevated with significant myocardial damage, whereas the heat-labile fraction increases in the serum with destruction of liver parenchyma. The relative ratio of heat-stable to total

The use of cellulose acetate for the electrophoretic separation and quantitation of serum lactic dehydrogenase isozymes in normal and pathologic states

Normal and abnormal lactic dehydrogenase (LDH) isozyme distribution in serum was studied using cellulose acetate electrophoresis with a p-iodonitro tetrazolium violet (INT) stain, and a graphing procedure devised to permit rapid visualization and evaluation of the electrophoretograms. This diagnostic technique was validated by employing the system to analyze sera from 7 patients with acute myocardial infarct and 7 patients with parenchymatous liver disease. In each case elevation was noted in the appropriate tissue specific isozyme (LDH 1 and LDH 5 respectively). LDH isozyme patterns in 5 of 7 patients with pneumonia showed a modest elevation of LDH 1. Serial LDH isozyme patterns of 14 patients with acute pulmonary embolism, in 12 of whom total LDH was elevated, displayed a normal distribution. It is concluded that if tissue-specific LDH isozymes are released by the lung after embolization, their serum concentrations do not reach diagnostically useful levels.

Influence of oxygen on the lactate dehydrogenase isozyme pattern in chang liver cells

The influence of oxygen on lactate dehydrogenase isozyme pattern has been studied in mammalian cells cultured in vitro. A shift in isozyme pattern towards the muscle type (LDH-5) occurred in cells cultured in tightly closed, un-aerated flasks. No marked shift towards the heart type (LDH-1) was observed in cells cultured under high oxygen tension. The reported shift does not seem to be caused by changes in hydrogen ion concentration, rate of respiration or the ATP level.

Stability of lactate dehydrogenase isozyme patterns in penguins.

PENGUINS were chosen for this investigation because of their highly specialized adaptation to an aquatic life and because of the extreme physiological conditions they are subjected to during the breeding season. One of the most abundant species is the Adelie penguin, Pygoscelis adeliae, which has a circumpolar distribution south of the Antarctic pack-ice. Unlike other birds this species endures a prolonged fast averaging 6 weeks during incubation1 and another fast of shorter duration when it moults. At both times they may lose more than 40 per cent of their body-weight. Though flightless, their pectoralis muscles are well developed for extensive swimming and diving at sea.

Lactic dehydrogenase and radiation-induced lymphoid leukaemia in mice.

The enzyme activity and the electrophoretic characteristics of lactic dehydrogenase (LDH) in the plasma and different tissues from the mice with radiation-induced lymphoid leukaemia were examined and compared with those obtained from the normal mice. The LDH activity was abnormally increased in the leukaemic plasma. A considerable elevation of the enzyme level was also found both in the leukaemic spleen and in the lymphocytes isolated from it, but not in the liver, kidney, heart and muscle. LDH isozyme patterns were obtained by agar-gel electrophoresis. Each tissue exhibited a characteristic distribution of LDH activity among the separated isozymes. Leukaemic plasma contained much more LDH-5 than normal plasma, showing the pattern similar to that obtained from leukaemic spleen. Kidney and heart from leukaemic mice indicated no difference in the LDH-patterns as compared with those from normal mice.

Lactate and pyruvate concentrations in exercised ischemic canine muscle: relationship of tissue substrate level to lactate dehydrogenase isozyme pattern.

Lactate and pyruvate concentrations in exercised ischemic canine muscle: relationship of tissue substrate level to lactate dehydrogenase isozyme pattern.

The activity of lactate dehydrogenase isozymes during thyroxine-induced tadpole metamorphosis.

A new improved method to quantitate the amount of the isozymes of lactate dehydrogenase (LDH) has been devised. The method is sensitive and very reproducible. This method has been employed for studies on LDH isozymes during thyroxine-induced tadpole metamorphosis. Only one isozyme is present in tadpole liver whereas three isozymes are present in tadpole tail and brain. Thyroxine treatment produced a decrease of the total LDH activity of tadpole liver, tail, and brain; however, the relative amount of the isozyme F3in tail and brain is the only fraction which shows a decrease. The F1and F2fractions show an increase in relative amount. Thalidomide has no influence on the isozyme pattern of LDH in thyroxine-induced metamorphosis of the tadpole.

Studies on Lactate Dehydrogenase Isozymes of Body Fluids (I)

There have been difficulties in separating first and second fractions near the cathode in analysing serum lactate dehydrogenase (LDH) isozymes using conventional agar-gel electrophoretic methods. In order to obtain clear separation as well as reliable pattern of LDH isozymes, studies were performed by means of agar gel electrophoresis followed by the staining using nitroblue tetrazolium. The method for routine electrophoretic analysis of LDH isozymes for various body fluids or extracts was established.1. Clear separation of LDH isozyme patterns could be obtained by improved cooling device as well as by the choice of proper electrophoretic and staining conditions.2. It was found that the process for preparation of agar plate was important in order to obtain reproducible results.3. Proper quantity of sample to use for LDH isozyme studies was examined using filter paper method by Ogita.4. Ressler's staining condition was found to be most sensitive and reliable for our method.

Lactate dehydrogenase isozyme patterns of human platelets and bovine lens fibers.

Human platelets and bovine lens fibers contain lactate dehydrogenase-3 (LDH-3) as the predominant isozyme but only very faint traces of LDH-5. Since the platelets and lens fibers, like mature human erythrocytes, lack a nucleus, the results strengthen the case for a previously developed association between LDH-5 and the cell nucleus. These three cell types are mainly anaerobic, and therefore their isozyme patterns are incompatible with the theory that anaerobic tissues exhibit predominantly LDH-5 and aerobic tissues mainly LDH-1.

Lactate dehydrogenase isozyme patterns of fish.

AbstractRepresentatives of 30 species of fish were examined for their content of LDH isozymes. One major isozyme system was found in all fish. In addition, two minor systems restricted to eyes and to gonads were found in many fish. Fish may be classified into four groups on the basis of their possession of one, two, three, or five major isozymes of LDH. The major isozyme patterns can be attributed to the polymers of two protein subunits under the control of two genes, as in mammals and birds, but the variety of heteropolymers produced varies in different species. The fluke and other flatfish are exceptional in that they synthesize only one kind of subunit which polymerizes to form a single variety of LDH. All other fish produced at least two major isozymes presumably the homopolymers of A and B subunits. The three‐isozyme fish produce, in addition, a single heteropolymer. A few fish produce three heteropolymers and two homopolymers to produce the characteristic pattern of five isozymes seen in mammals.In populations of the whiting, which has five major isozymes, two mutant alleles at the B locus were discovered. Each of these alleles produced polypeptides with characteristic electrophoretic mobilities. Consequently, heterozygous individuals contained more than 15 isozymes.A variety of minor isozymes that appear on zymograms may represent modifications of the major isozymes. However, the minor isozyme systems of the gonad and the eye seem to be genetically distinct molecular systems, separate from and in addition to the major isozyme system.

Formation of human lactate dehydrogenase isozyme patterns in vitro.

Formation of human lactate dehydrogenase isozyme patterns in vitro.

ELECTROPHORETIC PATTERN OF MUSCLE LACTIC DEHYDROGENASE IN VARIOUS DISEASES.

Introduction THE ELECTROPHORETIC pattern of the enzyme lactic dehydrogenase (LDH) is composed of several bands which are believed to be different molecular forms of the enzyme and have been called isozymes. 17 It has been suggested that these isozymes result from various tetrameric associations of two subunits referred to as A and B by Markert, 1,15 and as M and H by Cahn et al. 4 Experimental evidence supporting this idea has been presented recently. 16 The electrophoretic pattern of LDH isozymes is tissue specific. Wroblewski and Gregory 23 showed that of all the different tissues they examined no two appeared to have exactly the same LDH pattern. The LDH isozyme pattern of human skeletal muscle is composed of five bands. The cathodic or most slowly migrating band (LDH-5) predominates whereas the anodic or most rapidly migrating bands (LDH-1 and LDH-2) are reduced. Dreyfus et al 9 and Wieme