Effects of Irradiation or Traumatic Injuries on Propionate Metabolism in Rats

[摘要] The rate of 14CO2 production in vivo by rats after injection with 10 µCi of 1-14C-propionate is useful in selecting uniform groups of animals for studies of experimental injuries and in investigating dose—response relationships in animals exposed to injury. The response appeared to be most sensitive to lung injury induced by air-blast, but was also sensitive to critical levels of irradiation or thermal exposure. Irradiation with 60Co γ-irradiation significantly depressed 14CO2 production, the degree and persistence being doserelated. Critical burn injuries resulted in decreased rates of 14CO2 production, which decreased as the clinical condition of animals deteriorated. Because the most significant decrease occurred within the first 30 min, measurement of the initial rate of 14C-propionate utilization was sufficient to detect altered metabolic states. High-resolution radioanalyses of urinary organic acids show the major ones excreted to be propionate and its immediate catabolites, methylmalonate and succinate, in both control animals and animals exposed to experimental injuries. These results suggest that propionate metabolism may be one of the sites in intermediary metabolism that is sensitive to alteration by experimental injuries and thus may be one of the more sensitive metabolic indicators.

[学科分类] 过敏症与临床免疫学