Fishman Wh, B. Springer, R. Brunettei
Apr 1, 1948
Citations
1
Influential Citations
391
Citations
Quality indicators
Journal
The Journal of biological chemistry
Abstract
Previous conditions in which phenolphthalein glucuronide was employed as substrate (1) have proved unsatisfactory for the determination of glucuronidase in plasma, serum, and laked blood cells. Thus, low glucuronidase activities such as frequently occur in plasma could not be accurately measured or even approximated, owing to a combination of circumstances; i.e., too short an incubation period often coupled with interference by a turbid state of the plasma and the presence in it of biliary and carotenoid pigments. Moreover, solutions of laked erythrocytes could not be assayed because of the red color of the hemoglobin. These d8iculties have now been largely overcome by the introduction of a deproteinizing procedure and by otherwise modifying the conditions of assay. It has been possible also to simplify greatly the biosynthetic process of manufacturing the substrate, phenolphthalein glucuronide, which is now in demand.’ The interpretation of blood glucuronidase values is handicapped by our lack of knowledge concerning the factors which control the level of this enzyme in the blood; e.g., we do not know to what extent the plasma glucuronidase is influenced by hormonal factors. The nature and significance of the distribution of /3-glucuronidase between the plasma and the formed elements of the blood is likewise not understood. As a result of observations made on blood glucuronidase with the improved assay technique, some of the desired information has been obtained. An account of the method and its use in these experiments is given in the present paper.