Rat brain glutathione S-transferases.

Characterization and Localization of Glutathione‐S‐Transferases in Rat Brain and Binding of Hormones, Neurotransmitters, and Drugs

“…General strategies for purification of GSTs from extrahepatic tissues, particularly those with lower levels of the enzymes or higher ratios of GSH to protein, may be patterned according to procedures described here for purification of the brain isoenzymes. For example, specific activities of brain GSTs with 1 -chloro-2,4-dinitrobenzene as a substrate (Table 1) were commensurate with those of the liver enzymes and much higher than activities reported earlier for purified brain preparations (Kubota et al, 1985;Li et al, 1986;Singh et al, 1987). It is likely that the use of a lysyl-GSH affinity matrix that may be eluted efficiently with S-methyl-GSH, rather than affinity matrices that require tightly bound alkyl-GSH derivatives for elution, is best suited for smaller scale purifications from tissues where GST levels are relatively low.…”

“…In unfractionated brain homogenate supernatants, most of the GST enzymatic activities elute as anionic components [ Fig. 3A and see Kubota et al (1985)], in contrast to patterns obtained with purified GSTs where both Y, and Ybl are cationic on the same column (Fig. 1).…”

“…Hepatic forms have generally been emphasized in most studies, but some potential functions of GSTs in detoxication of xenobiotics in brain have also been investigated (Dixit et al, 1981;Das et al, 1981;Maker, 1983;Srivastava et al, 1984;Mesuil and Testa, 1984). Studies on GST isoenzyme patterns in rat brain have recently appeared (Kubota et al, 1985;Li et al, 1986;Singh et al, 1987), but very little is known about binding, cellular distribution, and other characteristics of brain GSTs. In this report the localization and properties of rat brain GSTs are considered in terms of their potential capacity to control transport and modulate the action of steroid and thyroid hormones, neurotransmitters, drugs, and other compounds in the CNS.…”