Effect of phenobarbital on UDP-glucosyltransterase activity and phenolic glucosidation in the mollusc Arion ater

Disposition and biotransformation of pentachlorophenol in the red abalone (Haliotis rufescens)

“…When gut segments from related freshwater/terrestrial gastropod molluscs (H. pomatia and Arion ater) were exposed to 4-nitrophenol and o-aminophenol, respectively, they exclusively detoxified the substrates by glucosidation (Dutton 1966, Leakey andDutton 1975). No other metabolic activity was observed, and UDP-glucosyltransferase activity was increased by pretreatment with the metabolic inducer phenobarbital (Leakey and Dutton 1975).…”

“…When gut segments from related freshwater/terrestrial gastropod molluscs (H. pomatia and Arion ater) were exposed to 4-nitrophenol and o-aminophenol, respectively, they exclusively detoxified the substrates by glucosidation (Dutton 1966, Leakey andDutton 1975). No other metabolic activity was observed, and UDP-glucosyltransferase activity was increased by pretreatment with the metabolic inducer phenobarbital (Leakey and Dutton 1975). At 37"C, both UDP-glucosyltransferase and UDPglucuronosyltransferase activities were observed in digestive gland microsomes from the gumboot chiton (Cryptochiton stellera3 when exposed to p-nitrophenol (Schlenk and Buhler 1988).…”

Hepatic ontogenesis

“…Little if any glucuronidation of xenobiotics occur in invertebrates (27). UDP-glucosyltransferase in invertebrates has assumed the major detoxification role of UDPglucuronyltransferase which is important in vertebrates.…”

“…UDP-glucosyltransferase in invertebrates has assumed the major detoxification role of UDPglucuronyltransferase which is important in vertebrates. After phenobarbital induction in animals as the slug (Arion ater), UDP-glucosyltransferase activity was increased without detectable levels of UDP-glucuronyltransferase (27). One exception may be the apparent ability of the blue crab's midgut gland to transfer enzymatically glucuronic acid to p-nitrophenol (28).…”