Effects of cold preservation and reperfusion on microsomal cytochrome P-450-linked monooxygenase system of the rat liver.
The effects of cold preservation and reperfusion of the liver on the hepatic microsomal cytochrome P-450-linked monooxygenase system (P-450 system) were investigated. Rat livers were preserved with cold University of Wisconsin solution for 0, 12, 24, 36, and 48 hr. Half of them in 0-, 24-, and 48-hr groups were reperfused for 1 hr at 37 degrees C with oxygenated Krebs-Henseleit buffer. After preservation or reperfusion, the liver microsomes were prepared and the concentration of each component of the P-450 system [NADPH-cytochrome b5 reductase (b5 reductase), cytochrome b5 (b5), NADPH-cytochrome P-450 reductase (P-450 reductase) and cytochrome P-450 (P-450)] and their drug metabolizing activities and concentration of apo-cytochrome P-450 2E1 (apo-P-450 2E1) were measured. After 48-hr preservation, b5 concentration did not decrease, whereas the concentration of P-450, P-450 reductase, and b5 reductase decreased from 0.865 to 0.676 nmole/mg protein, from 0.262 to 0.233 micromole/mg protein/min and from 5.34 to 4.86 micromole/mg protein/min, respectively. During cold preservation, the activities of p-nitroanisole O-demethylase and aniline p-hydroxylase did not change. Aminopyrine N-demethylase activity was inhibited from 4.45 to 3.34 nmole/mg protein/min after 48-hr cold preservation. Apo-P-450 2E1 was gradually decreased during cold preservation. Reperfusion caused a further decrease in the activities and concentration of the components of the P-450 system and concentration of apo-P-450 2E1 to 80-90% after 1-hr reperfusion. It was suggested that the prolonged preservation caused deterioration of the P-450 system and the loss of the abilities of metabolism and detoxication of xenobiotics.
Izuishi
K
K
First Department of Surgery, Kagawa Medical School, Miki-cho, Kita-gun, Japan.
Ichikawa
Y
Y
Hossain
M A
MA
Maeba
T
T
Maeta
H
H
Tanaka
S
S
D000818:Animals; D003080:Cold Temperature; D003577:Cytochrome P-450 Enzyme System / Q000032:analysis*; D015786:Cytochromes b5 / Q000032:analysis; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008297:Male; D008862:Microsomes, Liver / Q000201:enzymology*; D009251:NADPH-Ferrihemoprotein Reductase / Q000032:analysis; D009926:Organ Preservation; D051381:Rats; D017207:Rats, Sprague-Dawley; D015424:Reperfusion
D015786:Cytochromes b5; D003577:Cytochrome P-450 Enzyme System; D007770:L-Lactate Dehydrogenase; D009251:NADPH-Ferrihemoprotein Reductase