[The effect of x-ray irradiation on UDP glucuronyltransferase activity in the liver microsomes of rats].

It was shown that X irradiation of male and female rats with dose of 7 Gy causes phase alterations of UDP-glucuronyltransferase activity (p-nitrophenol glucuronidation was analysed) in liver microsomal fraction: 24 hr after irradiation decrease (to 45.7 +/- 6.4 and 60.2 +/- 8.6% of norm correspondingly) followed by 72 hr after irradiation increase (to 190.5 +/- 4.8 and 155.4 +/- 12.2% of norm) and normalization of the enzyme activity 120-168 hr after irradiation. Direct dependence of the 24 hr after irradiation enzyme activity decrease on exposure dose (for males in the dose range of 2-10 Gy, for females in the range of 5-12 Gy) due to reducing of active form of UDP-glucuronyltransferase (UDPGT) was established. It was found that glucuronyltransferase activity increase 72 hr after irradiation occurred against the background of normalization of UDPGT active form level.