Effect of alkyl phosphates on β-glucuronidase in rats: Release of β-glucuronidase from liver microsomes into serum

Abstract

Injection of alkyl phosphates elicits an elevation of rat serum β-glucuronidase activity without altering levels of serum lysosomal hydrorases and cholinesterase. Among alkyl phosphates tested, dibutyl phosphate and tributyl phosphate were much more effective and the activities increased 120- and 90-fold of control activity after 1 and 2 hr, respectively. Subfractionation study showed that after the injection of tributyl phosphate the increase in serum β-glucuronidase activity correlated with a depression in the activity of liver microsomal β-glucuronidase but not lysosomal one. Density gradient subfractionation study suggested liver microsomes as the main source of increased serum β-glucuronidase.