Szutowski M M, Brzdekiewicz D
Zakładu Tokaykologii Instytutu Biofarmacji, Akademii Medycznej w Warszawie.
Folia Med Cracov. 1990;31(3):175-84.
Methanol interacts with cytochrome P-450 to produce the reversed type I spectral change. In the presence of type I substrate n-heptane, the methanol induced spectrum disappears without detectable effects of interaction suggesting that methanol is a very weak ligand for heme iron of cytochrome P-450. Methanol strongly lowers the apparent spectral dissociation constant (Ks app) of n-heptane binding with rat liver cytochrome P-450 both in control and C6-C9 petroleum fraction inhaled group. In control group, titration of cytochrome P-450 with methanolic solutions of n-heptane does not change the maximal spectral interaction (Amax) observed with pure n-heptane. However in the inhaled group during titration of induced cytochrome P-450 with methanolic solutions of n-heptane an additional type I spectral change is observed. Thus addition of "equivalent" amounts of methanol into the reference cuvette during titration with methanolic solutions overestimates the true magnitude of type I spectral change of cytochrome P-450 with n-heptane.
甲醇与细胞色素P - 450相互作用产生逆向I型光谱变化。在I型底物正庚烷存在的情况下，甲醇诱导的光谱消失，未检测到相互作用的影响，这表明甲醇是细胞色素P - 450血红素铁的一种非常弱的配体。在对照组和吸入C6 - C9石油馏分组中，甲醇均强烈降低了正庚烷与大鼠肝脏细胞色素P - 450结合的表观光谱解离常数（Ks app）。在对照组中，用正庚烷的甲醇溶液滴定细胞色素P - 450不会改变用纯正庚烷观察到的最大光谱相互作用（Amax）。然而，在吸入组中，在用正庚烷的甲醇溶液滴定诱导的细胞色素P - 450期间，观察到额外的I型光谱变化。因此，在用甲醇溶液滴定时，向参比比色皿中加入“等量”甲醇会高估细胞色素P - 450与正庚烷的I型光谱变化的真实幅度。
