Effect of diflubenzuron on the incorporation of UDP-N-acetyl-[3H]glucosamine (UDP-[3H]NAGA) to chitin in permeabilized, and isolated integuments from the newly molted American cockroach Periplaneta americana.
1. Diflubenzuron (DFB) was found to inhibit the incorporation of UDP-N-acetyl-[3H]glucosamine (UDP-[3H]NAGA) to chitin in permeabilized and isolated integument from newly molted American cockroach. 2. The favorable experimental conditions demonstrating the effect of diflubenzuron were: 10 mM phosphate, low calcium concentration (10(-6) M-10(-8) M), high potassium concentration (> 100 mM), and high pH (> or = 7). 3. The action of diflubenzuron was completely erased by preincubating the isolated integument with valinomycin, FCCP, or A23187. 4. By lowering the external pH to 5.2, it was also possible to reduce the rate of UDP-[3H]NAGA incorporation to the extent that DFB's effect was no longer recognizable. 5. Both Cs+ and Rb+ could replace K+ in maintaining a high level of chitin synthesis and the inhibitory action of DFB under the optimum conditions.
Nakagawa
Y
Y
Department of Environmental Toxicology, University of California, Davis 95616.
Matsumura
F
F
D000818:Animals; D000001:Calcimycin / Q000494:pharmacology; D002259:Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone / Q000494:pharmacology; D002686:Chitin / Q000096:biosynthesis*; D004132:Diflubenzuron / Q000494:pharmacology*; D004072:Digitonin / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D010526:Periplaneta / Q000378:metabolism*; D014537:Uridine Diphosphate N-Acetylglucosamine / Q000378:metabolism*; D014634:Valinomycin / Q000494:pharmacology
D002686:Chitin; D014634:Valinomycin; D002259:Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone; D000001:Calcimycin; D014537:Uridine Diphosphate N-Acetylglucosamine; D004132:Diflubenzuron; D004072:Digitonin