Micromethod for determination of lactate dehydrogenase isoenzyme C4 activity in human seminal plasma.

1983 ◽  
Vol 29 (8) ◽  
pp. 1518-1521
Author(s):  
G P Butrimovitz ◽  
F Farina ◽  
I Sharlip
Keyword(s):  
Lactate Dehydrogenase ◽  
Seminal Plasma ◽  
Male Fertility ◽  
Zero Order ◽  
Order Kinetic ◽  
Human Seminal Plasma ◽  
Human Spermatogenesis ◽  
Sensitivity Specificity ◽  
Lactate Dehydrogenase Isoenzymes

Abstract We have developed an automated enzymatic assay for LDH-C4, a lactate dehydrogenase (EC 1.1.1.27) isoenzyme found exclusively in spermatozoa, as a marker of human spermatogenesis. LDH-C4 activity is assayed bichromatically in the Abbott ABA-100 spectrophotometer, with 2-oxohexanoate as substrate. As many as 27 samples (2.5 microL) of human seminal plasma can be analyzed sequentially, with apparent zero-order kinetic conditions and with a precision (CV) of 5%. The apparent Km for the 2-oxohexanoate reaction is 11.2 mmol/L. Electrophoretic and enzymatic studies indicate that LDH-C4 acts on this substrate to produce hydroxyhexanoate, in contrast to lactate dehydrogenase isoenzymes 1 and 5--further evidence for the uniqueness of LDH-C4. The sensitivity, specificity, and speed of this assay system makes it practicable for studies on, and evaluation of, male fertility.

Simple, rapid determination of zinc and acid phosphatase in seminal plasma with an ABA-100 bichromatic analyzer.

1988 ◽  
Vol 34 (8) ◽  
pp. 1605-1607 ◽  
Author(s):  
M Gavella
Keyword(s):  
Acid Phosphatase ◽  
Male Infertility ◽  
Seminal Plasma ◽  
Rapid Determination ◽  
Assay System ◽  
Human Seminal Plasma ◽  
Automated Assay ◽  
Sensitivity Specificity

Abstract I describe an automated assay for zinc and acid phosphatase in seminal plasma. These, which are markers of the function of the prostate, were assayed bichromatically with an Abbott ABA-100 analyzer. As many as 25 samples of human seminal plasma can be analyzed sequentially with CVs of 3.1% for zinc and 1.5% for acid phosphatase. The sensitivity, specificity, and speed of this assay system make it practicable for use in investigation of male infertility.

Simple, rapid enzymatic determination of glycerophosphocholine in human seminal plasma.

1988 ◽  
Vol 34 (1) ◽  
pp. 106-109 ◽  
Author(s):  
H J Chap ◽  
J P Moatti ◽  
R Mieusset ◽  
M Nieto ◽  
G Laneelle ◽  
...  
Keyword(s):  
Seminal Plasma ◽  
Substrate Concentration ◽  
Male Fertility ◽  
Choline Oxidase ◽  
New Method ◽  
Human Seminal Plasma ◽  
Enzymatic Determination ◽  
Analytical Recovery ◽  
Free Choline

Abstract We have devised a new enzymatic determination of sn-glycero-3-phosphocholine (GPC) in human seminal plasma. This is based on GPC hydrolysis by a phosphodiesterase (PDE), free choline being then determined by the choline oxidase method. The whole procedure involves a first incubation in the presence of choline oxidase and catalase, to eliminate the excess of choline present in seminal plasma (10-fold, compared with GPC). Absorbance and concentration are linearly related up to at least 100 nmol per assay, analytical recovery ranges between 89% and 105%, and intra- and interassay CVs are 3.2% and 5.6%, respectively, at the highest substrate concentration. Using this procedure, we found seminal plasma from 21 fertile men to contain 5.22 (SD 3.33) mumol per ejaculate--within the same range as previously reported values obtained chromatographically. After vasectomy, GPC in seminal plasma decreased to 28% of its original value, as determined in 10 volunteers. Thus this new method displays appropriate characteristics of specificity, reliability, and convenience, allowing its use in routine evaluation of male fertility.

Automated kinetic determination of lactate dehydrogenase isoenzymes in serum.

1977 ◽  
Vol 23 (10) ◽  
pp. 1928-1930 ◽  
Author(s):  
L H Bernstein
Keyword(s):  
Lactate Dehydrogenase ◽  
Kinetic Method ◽  
Previous Method ◽  
Kinetic Determination ◽  
Steady State Kinetic ◽  
Enzyme Subunits ◽  
Isoenzyme Composition ◽  
State Kinetic ◽  
Lactate Dehydrogenase Isoenzymes

Abstract A steady-state kinetic method has been revised for measuring lactate dehydrogenase isoenzyme activities, which relates the inhibition of heart-type isoenzyme activity to the overall isoenzyme composition of the enzyme subunits. The method depends on the pH-dependent formation of an inhibitory ternary complex by the heart-type isoenzyme with NAD+ and pyruvate (if the reaction is measured by NADH oxidation). A preincubation step in the previous method is eliminated. The isoenzymes are measured by measuring the reduction of pyruvate in two different concentrations, which favor either the total or fractional activity, depending on the concentrations of pyruvate and the percentage of heart-type subunits. The method has been adapted to a centrifugal analyzer, which has speeded automated isoenzyme determinations, with an accuracy comparable to that for electrophoretic methods.

Ten electrophoretic methods compared with a selected method for quantifying lactate dehydrogenase isoenzymes in serum.

1988 ◽  
Vol 34 (9) ◽  
pp. 1885-1890 ◽  
Author(s):  
G C Moses ◽  
M L Ross ◽  
A R Henderson
Keyword(s):  
Lactate Dehydrogenase ◽  
Reference Method ◽  
Average Difference ◽  
Correlation Analyses ◽  
Different Types ◽  
Lactate Dehydrogenase Isoenzymes

Abstract Using the Selected Method of McKenzie and Henderson (Selected Methods Clin Chem 1983;10:59-67) as a reference method, we compared the performance of 10 commercially available methods for determination of lactate dehydrogenase (LD, EC 1.1.1.27) isoenzymes. Results were expressed as percentage of total LD activity, as determined with two different types of densitometers shown to have an average difference less than 1.4% for each isoenzyme. All methods gave generally comparable results, as judged by Bland-Altman plots and correlation analyses. However, in general, estimates by the commercial methods for LD-1, LD-2, and LD-3 were lower, and for LD-4 and LD-5 were higher than with the Selected Method. The overall CV was less than 20% for all methods and isoenzymes, except for LD-4 and LD-5 by the Beckman Paragon, Helena LD-VIS, Gel LDH, Gel PC, and Iso Dot, Gelman LDH Isozyme, and Sebia Hydragel assays, for which it was greater than 20%. Overall, accuracy was best with the Helena Iso Dot and LD-VIS assays, followed by the Corning LD Flur assay; accuracy was poorest with the Gelman LDH Isozyme, Sebia Hydragel, and Beckman Paragon assays.

scholarly journals The determination of lactate dehydrogenase isoenzymes in normal human muscle and other tissues

1967 ◽  
Vol 105 (2) ◽  
pp. 599-604 ◽  
Author(s):  
A. E. H. Emery
Keyword(s):  
Lactate Dehydrogenase ◽  
Gel Electrophoresis ◽  
Human Muscle ◽  
Starch Gel Electrophoresis ◽  
Fibrous Connective Tissue ◽  
Starch Gel ◽  
Normal Human ◽  
Lactate Dehydrogenase Isoenzymes ◽  
Good Agreement

1. A technique has been developed, based on preferential inhibition by urea, for determining the amounts and proportions of the M and H sub-units of lactate dehydrogenase (referred to as LDH-M and LDH-H respectively) in human tissues, including muscle. 2. There was good agreement between the results obtained with urea inhibition and those obtained with starch-gel electrophoresis. 3. With increasing age there was a significant decrease in the total amount of lactate dehydrogenase and the amount of LDH-M in skeletal muscle. This could not be accounted for by the replacement of functioning muscle tissue by fibrous connective tissue. 4. The proportion of LDH-M was less in certain muscles (e.g. soleus and extra-ocular) than in other muscles (e.g. gastrocnemius and rectus abdominis). 5. The proportions of LDH-M and LDH-H did not differ significantly in different superficial limb muscles and were not significantly affected by either age or sex. 6. Specimens of muscle from 86 different individuals (all Europeans) have been subjected to electrophoresis, but no variants of lactate dehydrogenase isoenzymes have been found.

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