Studies on β-glucuronidase. 3. The influence of age, partial hepatectomy and other factors on the β-glucuronidase activity of rat liver

Publisher Website
Google Scholar
Abstract
In rats the liver beta-glucuronidase activity is low at birth, rises to a max. at around 25-30 days and then falls slightly to the adult level around 80-90 days after birth. The use of dexoyribosenucleic acid (DNA) as an index of cell number in the tissue, along with the allometric method of analysis, indicates that the beta-glucuronidase content of the liver cell increases up to 18 days after birth and thereafter remains constant. A rise in beta-glucuronidase activity in rat liver to 60-70 above normal occurs 4 days after partial hepatectomy and the high level of activity persists for at least the next 6 days. An estimation of the growth rate of liver cells, using the DNA content, indicates that the period of max. cellular proliferation is around 3 days after operation. Sham operation causes a slight fall in rat liver beta-glucuronidase activity which returns to normal within 4 days. Adrenalectomy causes no alteration in rat liver beta-glucuronidase activity during the 1st 4 days after operation. Peanut oil injn. causes a profound increase in rat liver beta-glucuronidase activity, and it is concluded that the smaller rise seen after injn. of CC14 in peanut oil is to be interpreted as an actual loss of beta-glucuronidase from the liver. Fatty infiltration of the liver caused by a high-fat, low-protein diet causes a slight rise in rat liver beta-glucuronidase activity. These findings are discussed in reference to previous work on the subject and it is concluded that in the rat increased beta-glucuronidase activities are not to be related to increased cellular proliferation as suggested by Levvy et al. (1948) for mice.