The Electrical Properties of the Anterior Stomach of the Larval Mosquito (Aedes Aegypti)

Abstract

The electrical properties of the anterior stomach of the larval mosquito (Aedes aegypti) were determined. At late times after cannulation, the intraluminal space constant was 936 mm, which is almost as long as the isolated tissue itself. At this time, the resistance of the apical cell membranes dominates the transcellular resistance; it is approximately 14 times the resistance of the basal cell membrane. Two physiologically distinct epithelial cell types were identified. One type has a stable basal potential of approximately 65 mV and responds to 5-hydroxytryptamine with hyperpolarization. The second cell type initially shows a basal potential of 100mV. However, this basal potential decays in the first few minutes in parallel with the decay of the transintestinal potential. This latter cell type does not respond to 5-hydroxytryptamine. Key words: mosquito, Aedes aegypti, midgut, larva, intracellular potential, 5-hydroxytryptamine.