The response of intact Strongyloides ratti infective (L3) larvae to substrates and inhibitors of respiratory electron transport.
Live, intact third-stage larvae (L3s) of Strongyloides ratti in the absence of exogenous substrates consumed oxygen at a rate (E-QO2) of 181.8 +/- 12.4 ng atoms min-1 mg dry weight-1 at 35 degrees C. Respiratory electron transport (RET) Complex I inhibitor rotenone (2 microM) produced 33 +/- 6.5% inhibition of the E-QO2. Unusually the rotenone-induced inhibition was not relieved by 5 mM-succinate. The E-QO2 of intact L3s was refractory to RET Complex III inhibitor antimycin A at 2 microM; 4 microM-antimycin inhibited less than or equal to 10% of the E-QO2. The electron donor couple ascorbate/TMPD augmented the E-QO2 in the presence of rotenone (2 microM) and antimycin A (4 microM) by 110%. Azide (1 mM) stimulated the antimycin A refractory QO2 by 36.6 +/- 7.2% which was only partially inhibited by 1.0 mM-KCN (IC50 = 0.8 mM). The data suggest the presence of classical (CPW) and alternate (APW) electron transport pathways in S. ratti L3s.
Mendis
A H
AH
School of Biomedical Sciences, Curtin University of Technology, Perth, Australia.
Armson
A
A
Thompson
R C
RC
Grubb
W B
WB
D000818:Animals; D000968:Antimycin A / Q000494:pharmacology; D001386:Azides / Q000494:pharmacology; D004579:Electron Transport / Q000187:drug effects; D007814:Larva / Q000378:metabolism; D010101:Oxygen Consumption / Q000187:drug effects; D011190:Potassium Cyanide / Q000494:pharmacology; D012402:Rotenone / Q000494:pharmacology*; D013321:Strongyloides / Q000187:drug effects / Q000378:metabolism*
D001386:Azides; D012402:Rotenone; D000968:Antimycin A; D011190:Potassium Cyanide