These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Hypoxic protection in paraquat poisoning.
    Author: Rhodes ML, Zavala DC, Brown D.
    Journal: Lab Invest; 1976 Nov; 35(5):496-500. PubMed ID: 994461.
    Abstract:
    Ingestion or injection of the herbicide paraquat (1,1'-dimethyl-4,4'-dipyridylium dichloride) has caused more than 120 deaths in humans. Most have been due to respiratory failure caused by pulmonary edema, hemorrhage, and atelectasis, or subsequent pulmonary fibrosis. Paraquat is concentrated in lung tissue and is believed to cause superoxide radical formation in the presence of oxygen and suitable electron donors. Exposure to increased concentrations of oxygen has been reported to accelerate the toxicity of paraquat. The therapeutic efficacy of a reduced oxygen environment was investigated by exposing paraquat-poisoned mice to 10% oxygen after stepwise drops from 14% oxygen. Sixty-one mice were given intraperitoneal injections of 27 mg. per kg. of paraquat. The 25 mice in hypoxia for 7 days had a 32% mortality rate versus a 78% mortality rate for the remainder of the mice in room air, p less than 0.01. After a dose of 20 mg. per kg. of paraquat administered intraperitoneally, 24 mice in hypoxia had a 25% mortality rate versus 51% for 35 animals in room air. Brief exposures of the hypoxic group to "normoxia" (room air) led to pulmonary edema and death. The continuous exposure of paraquat-poisoned animals to hypoxic environments was protective. This approach may be useful in other oxidant lung injuries.
    [Abstract] [Full Text] [Related] [New Search]