Abstract
In experiments with isolated epididymal fat cells, paraoxone caused a dose-dependent inhibition of lipolysis in the LD50 dose range (10−7 - 10−5 M). The inhibition occurred in unstimulated as well as stimulated lipolysis elicited by 10−6 M norepinephrine or 3 × 10−3 M dibutyryl-A-3′, 5′-MP. The type of inhibition showed a noncompetitive pattern at an apparent Ki = 1.1 × 10−6 M. Obidoxime, HS 3 and HS 6 did not abolish the 50% inhibition of maximum lipolysis elicited by 10−6 M paraoxone. Neither a reactivation nor a direct interaction between paraoxone and oximes was observed in this test system.
Zusammenfassung
Im LD50-Bereich (10−7 - 10−5 M) beeinflußte Paraoxon dosisabhängig die Lipolyse isolierter Fettzellen aus dem Nebenhoden-Fettgewebe von Ratten. Die nicht kompetitive Hemmung der Glycerinfreisetzung wurde sowohl bei der basalen, als auch bei der durch 10−6 M Noradrenalin oder 3 × 10−3 M Dibutyryl-A-3′, 5′-MP stimulierten Lipolyse beobachtet (K1 = 1,1 × 10−6 M). HS 3, Obidoxim oder HS 6 hatten keinen Einfluß auf die durch 10−6 M Paraoxon bewirkte etwa 50 %ige Hemmung der maximal stimulierten Lipolyse. Weder eine Reaktivierung noch eine Direktwirkung zwischen Paraoxon und den geprüften Oximen war in diesem Testsystem nachweisbar.
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Some of this work is part of the doctoral thesis of P. Selhorst.
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Peters, H.D., Selhorst, P., Dinmendahl, V. et al. Effect of paraoxon and antidotes on lipolysis of isolated fat cells. Arch Toxicol 30, 139–145 (1973). https://doi.org/10.1007/BF02425931
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DOI: https://doi.org/10.1007/BF02425931