Further examination of the selective toxicity of CCl4 in rat liver slices.
Lipid peroxidation and loss of enzymes located predominantly in either periportal or centrilobular hepatocytes were investigated in precision-cut liver slices from male Sprague-Dawley rats. Pretreatment of animals with 80 mg/kg phenobarbital for the site-specific enzyme studies enhanced and accelerated CCl4 toxicity in slices resulting from increased radical formation. Liver slices were exposed to 0.57 mM CCl4 by vaporization using a roller incubation system at 37 degrees C for a total of 9 hr. Conjugated diene formation, an index of lipid peroxidation, was detected 15 min following CCl4 administration and increased over time. Loss of cytochrome P450 occurred in a time-dependent manner relative to controls where levels in treated slices were 42% of controls at 9 hr. A 48-hr fast prior to termination increased intracellular K+ leakage relative to that present in slices from fed animals. Significant leakage of glucose-6-phosphate dehydrogenase and beta-glucuronidase from centrilobular hepatocytes occurred 9 hr following CCl4 administration. The content of the periportal enzymes (lactate dehydrogenase and sorbitol dehydrogenase) was unchanged in the same slices over the duration of the experiment. Reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide, a mitochondrial selective dye and indicator of viability, was significantly lower in treated slices from phenobarbital-treated animals at 9 hr relative to controls. These studies demonstrate that precision-cut slices are an ideal in vitro system for mechanistic studies and the investigation of site-specific toxicants since the integral architecture of the liver and cellular identity are maintained.
Azri
S
S
Department of Anesthesiology, University of Arizona, Tucson 85724.
Mata
H P
HP
Reid
L L
LL
Gandolfi
A J
AJ
Brendel
K
K
D000818:Animals; D002251:Carbon Tetrachloride / Q000633:toxicity*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D005215:Fasting; D007700:Kinetics; D015227:Lipid Peroxidation; D008099:Liver / Q000033:anatomy & histology / Q000187:drug effects* / Q000201:enzymology; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013778:Tetrazolium Salts / Q000378:metabolism; D013844:Thiazoles / Q000378:metabolism; D013997:Time Factors
D013778:Tetrazolium Salts; D013844:Thiazoles; D003577:Cytochrome P-450 Enzyme System; D002251:Carbon Tetrachloride; C022616:thiazolyl blue