6-PGD

Many isoenzymes have been identified from various human tissue sources however, our consideration will deal with six erythrocytic systems that have received routine crime laboratory status. These are phosphoglucomutase (PGM), adenylate kinase (AK), adenosine deaminase (ADA), glucose-6-phosphate dehydrogenase (G-6-PD), 6-phosphogluconate dehydrogenase (6-PGD) and erythrocytic acid phosphatase (EAP). 

This ability to obtain multiple isoenzyme information from a single electrophoretic zymogram is not new. Publications dealing with human genetic studies have listed PGM, AK, ADA and 6-PGD being determined on the same electrophoretic zymogram (6, 7). 

The position effect was discovered in D. melanogaster also using the example of transcriptional activity of structural genes. Particularly, transfer of the Pgd gene from the left chromosomal end, where this gene is located, to the heterochromatin region of the same chromosome as a result of the chromosomal rearrangement Dp(l f)R, reduced the activity of the 6-PGD enzyme which is under control of this... 

Table 16. 6-PGD phenotypes of the 36-h-48-h embryos Coturnix coturnix japonica. (After Ohno et al, 1968)...

An excess of PGD is added to the reaction mixture containing glucose 6-phosphate and NADP to assure that 2 moles of NADPH are produced per mole of glucose-6-phosphate oxidized (109). This method has been improved by Nicholson et. al (110) to make... 

Figure 16.24 Major prostaglandin and leukotriene products derived from arachidonic acid via the cyclooxygenase and 5-lipooxygenase pathways. Major enzymes 1, cyclooxygenase 2, hydroperoxidase 1 + 2, prostaglandin endoperoxidase synthetase 3, thromboxane synthetase 4, prostacyclin synthetase 5, 5-lipooxygenase 6, 9-ketoisomerase 7, PGH-PGF2a reductase 8, 11-ketoisomerase 9, PGE reductase 10, PGD reductase. (Reproduced by permission from Nelson NA, Kelly RC, Johnson, RA. Prostaglandins and the arachidonic acid cascade. Chem Eng News August 30-44, 1982.)...

The current system terms prostanoid receptors P receptors, which is preceded by a letter to indicate the most potent natural prostanoid at that particular receptor (hence the receptor at which PGD, is the most potent natural agonist is called the DP receptor and so on). This system was based initially upon a rigorous quantitative comparison of the agonist potencies of each of the natural prostanoids in tissue preparations chosen to avoid the problems associated with multiple receptor types. In addition, being aware of the limitations of agonists in receptor classification (111), efforts were made to identify specific prostanoid-receptor antagonists. A summary of the current state of prostanoid receptor classification is shown in Table 6.2. 

The structures of some DP receptor ligands are shown in Fig. 6.4. PGD, is not an inherently selective agonist it also has FP and TP receptor activity (188). The dehydration product of PGD2, PGJ2 O-deoxy-A -PGDg), (189)... 

We have developed a method to determine the five eicosanoids PGE / PGD, TXB2/ and 6-keto-PGF.j separately in one analysis as... 

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