Effects of isoflurane on the DNase I activity in an isolated enzyme preparation and on the DNase I-G actin complex.
Effects of isoflurane on the DNase I activity in an isolated enzyme preparation and in the DNase I-globular (G) actin complex were investigated. DNase I, DNase I-G actin complex, and G actin were exposed to various (0.2-4.0 vol%) isoflurane concentrations for 180 min. Thereafter, DNase I activity was determined. DNase I activity was inhibited in relation to time and concentration of isoflurane exposure. At concentrations ranging from 0.2 to 1.0 vol% of isoflurane inactive DNase I was activated in the DNase I-G actin complex. The DNase I inhibitor G actin showed a reduced capability to inhibit DNase I following isoflurane exposure. Albumin can inhibit the DNase I inactivation possibly by competition in the reactions between DNase I/albumin and isoflurane. After exposure to isoflurane the absorption maximum of DNase I was identical with the absorption maximum of heat-denatured DNase I. The results suggest a mechanism by which isoflurane may affect DNA in an indirect way at concentrations to which the patient is exposed during clinical anesthesia.
Department of Physiological Chemistry, University of Mainz, Federal Republic of Germany.
M
M
Reitz
A
A
von Pfeil
F
F
Hundt
E
E
Lanz
D000199:Actins / Q000037:antagonists & inhibitors* / Q000187:drug effects; D000818:Animals; D002021:Buffers; D002417:Cattle; D004249:DNA Damage; D003850:Deoxyribonuclease I / Q000037:antagonists & inhibitors* / Q000187:drug effects; D007530:Isoflurane / Q000494:pharmacology*; D010179:Pancreas / Q000201:enzymology; D011489:Protein Denaturation
D000199:Actins; D002021:Buffers; D007530:Isoflurane; D003850:Deoxyribonuclease I