Regulation of rat olfactory glutathione S-transferase expression. Investigation of sex differences, induction, and ontogenesis.
The glutathione S-transferases (GSTs) of rat olfactory epithelium have been characterised with regard to sex differences, induction, and developmental regulation, and compared to those of the liver. Olfactory cytosolic GST activity with 1-chloro-2,4-dinitrobenzene (CDNB) as substrate was similar in both male and female animals, and there were no differences in subunit profile. Administration of trans-stilbene oxide and beta-naphthoflavone had no effect on olfactory GST activity with CDNB, although phenobarbitone treatment resulted in a small, but significant, increase in activity (130% compared to controls). HPLC analysis of subunit profiles indicated that all three agents induced olfactory subunit 1b and decreased subunit 6. The effect of age (3 to 84 days) on both cytosolic and microsomal CDNB activity was examined. In the liver, cytosolic activity was low at 3 days and climbed steadily to reach maximal levels around 28 days, but microsomal activity was relatively constant at all ages. Olfactory cytosolic activity was similar at all ages; microsomal activity was low until 21 days and then increased to reach a maximum at 56 days. Changes in individual cytosolic subunits were assessed by SDS-PAGE followed by immunoblotting. The significance of these results with regard to putative physiological roles for olfactory GSTs is discussed.
Banger
K K
KK
School of Biomolecular Sciences, Liverpool John Moores University, Liverpool, U.K.
Lock
E A
EA
Reed
C J
CJ
D000375:Aging / Q000378:metabolism*; D000818:Animals; D003600:Cytosol / Q000201:enzymology; D004137:Dinitrochlorobenzene / Q000378:metabolism; D004790:Enzyme Induction; D005260:Female; D005982:Glutathione Transferase / Q000096:biosynthesis / Q000378:metabolism*; D008297:Male; D008861:Microsomes / Q000201:enzymology; D009297:Nasal Mucosa / Q000201:enzymology*; D051381:Rats; D017208:Rats, Wistar; D012737:Sex Factors; D013379:Substrate Specificity
D004137:Dinitrochlorobenzene; D005982:Glutathione Transferase