[Effect of phenobarbital on the cytogenetic activity of cyclophosphamide]

The effect of phenobarbital (PB, 2 and 80 mg/kg, 3 intraperitoneal injections) on the rate of chromosomal aberrations in the bone marrow cells of rats induced by a single intraperitoneal injection of cyclophosphamide (CP) in a dose of 25 mg/kg was studied. Activity of mixed function oxygenase (MFO) was evaluated from the content of cytochrome P450, b5 and activity of aniline hydroxylase. The rate of the cells with chromosomal aberrations in the bone marrow after combined action of PB and CP did not depend on the PB dose and was significantly higher as compared with CP action alone. After injection of 2 mg/kg, PB activity of MFO did not differ from that in control and increased 2 times after 80 mg/kg. Combined action of PB and CP did not induce any significant changes in activity of MFO compared with PB alone.