Strong alkalinization in the anterior midgut of larval yellow fever mosquitoes (Aedes aegypti): involvement of luminal Na+/K+-ATPase.

摘要: Recently, Na + /K -ATPase has been detected in the luminal membrane of anterior midgut larval yellow fever mosquitoes (Aedes aegypti) with immunohistochemical techniques. In this study, possible involvement ATPase strong alkalinization was investigated on level whole larvae, isolated and perfused preparations molecular protein. Ouabain (5 mM) did not inhibit capability intact to alkalinize their midgut. Also perfusion lumen ouabain result a significant change transepithelial voltage or capacity alkalinization. activity completely abolished when KCl substituted choline chloride, suggesting that enzyme cannot act as an ATP-driven /H exchanger. Altogether results present investigation indicate apical is direct importance for mosquitoes. Strong up pH values 12 observed regions many larvae endopterygote insects, including members orders Coleoptera, Diptera, Trichoptera Lepidoptera (for references see Clark, '99). Two tissues have studied especially intensively regard mechanisms capacities during past 20 years: tobacco hornworm (Manduca sexta) aegypti). For lepidopteran transport model established which V-type H -pumps (V-ATPases) energize luminal, electrogenic K /2H -exchangers, resulting active secretion