Pharmacological characterisation of apical Na+ and Cl- transport mechanisms of the anal papillae in the larval mosquito Aedes aegypti.

Autor(es): Del Duca Olimpia; Nasirian Azadeh; Galperin Vladimir; Donini Andrew

Resumo: The anal papillae of freshwater mosquito larvae are important sites of NaCl uptake, thereby acting to offset the dilution of the hemolymph by the dilute habitat. The ion-transport mechanisms in the anal papillae are not well understood. In this study, the scanning ion-selective electrode technique (SIET) was utilized to measure ion fluxes at the anal papillae, and pharmacological inhibitors of ion transport were utilized to identify ion-transport mechanisms. Na(+) uptake by the anal papillae was inhibited by bafilomycin and phenamil but not by HMA. Cl(-) uptake was inhibited by methazolamide, SITS and DIDS but not by bafilomycin. H(+) secretion was inhibited by bafilomycin and methazolamide. Ouabain and bumetanide had no effect on NaCl uptake or H(+) secretion. Together, the results suggest that Na(+) uptake at the apical membrane occurs through a Na(+) channel that is driven by a V-type H(+)-ATPase and that Cl(-) uptake occurs through a Cl(-)/HCO(3)(-) exchanger, with carbonic anhydrase providing H(+) and HCO(3)(-) to the V-type H(+)-ATPase and exchanger, respectively.

Palavras-Chave: Mosquito, Anal papillae, Ion transport, V-type H+-ATPase, Na+/K+-ATPase

Imprenta: The Journal of Experimental Biology, v. 214, pt. 23, p. 3992-3999, 2011

Identificador do objeto digital: 10.1242/jeb.063719.

Descritores: Aedes aegypti - Proteins

Data de publicação: 2011