β-d-Glucuronidase activity was studied histochemically in male hamster liver and kidney under varied conditions of nonfixation and fixation. Results were evaluated according to degrees of reaction, localization and diffusion. The reference point for total enzyme activity in these organs was determined biochemically in similarly nonfixed and fixed tissues. Consistent histochemical and biochemical results were obtained on nonfixed tissues and with material fixed in formalin-gum-sucrose. Organs fixed in formol-chloral hydrate and neutral buffered formalin were histochemically and biochemically negative for glucuronidase activity. Levels of β-d-glucuronidase in hamster liver and kidneys are low in comparison to known activity in the rat. Apparently, in the hamster, this enzyme is not present in sufficient quantity to give a positive reaction following partial inactivation by formol-chloral hydrate or neutral buffered formalin fixations. It is suggested that studies on tissues low in β-d-glucuronidase activity should incorporate both nonfixed and fixed tissues.
