Effect of dietary fat on pulmonary enzymes and toxicity during normobaric hyperoxia.
Weanling male rats were fed a semi-purified diet containing 10, 20, 40 or 60% of calories as fat having a constant polyunsaturated/saturated fatty acid ratio of 0.7. After 21-28 d of feeding, animals from each treatment group were exposed to pure oxygen at one atmosphere absolute for up to 72 h. Some animals were sacrificed after 0 or 48 h of oxygen exposure and lung tissue analyzed for the activities of the hexose monophosphate shunt and prostaglandin dehydrogenase/reductase. Other animals were exposed to hyperoxia until death. With increasing dietary fat content, the pre-exposure activities of the two enzymes decreased and oxygen-induced mortality increased. There was no dietary effect on enzyme activities after 48 h of hyperoxia. We concluded that both dietary fat content and the pre-exposure activity of prostaglandin dehydrogenase/reductase influenced the relative susceptibility to pulmonary oxygen poisoning.
D000818:Animals; D004041:Dietary Fats / Q000009:adverse effects*; D005224:Fats, Unsaturated / Q000494:pharmacology; D006600:Hexosephosphates / Q000378:metabolism*; D006911:Hydroxyprostaglandin Dehydrogenases / Q000032:analysis*; D008168:Lung / Q000201:enzymology* / Q000503:physiopathology; D008171:Lung Diseases / Q000139:chemically induced / Q000401:mortality*; D008297:Male; D010100:Oxygen / Q000633:toxicity*; D051381:Rats; D011919:Rats, Inbred Strains / Q000378:metabolism; D013997:Time Factors
D004041:Dietary Fats; D005224:Fats, Unsaturated; D006600:Hexosephosphates; D006911:Hydroxyprostaglandin Dehydrogenases; D010100:Oxygen