The Salivary Glands of Aedes Aegypti Histological–histochemical Studies

Abstract

The maturation of the salivary glands in adult mosquitoes was studied from histological preparations. A striking sexual dimorphism in the glands apparently reflects the blood-feeding habits of the female. The glands of the female undergo a dramatic development, following emergence, whereas those of the male remain small and show little change. Three main regions of secretory activity differentiate in the female: the necks and the acini proper of the lateral lobes and the acinus of the central lobe. These areas are characterized by histochemical criteria. A cycle of secretory activity occurs after ingestion of blood. The possible functions of the secretion products are discussed.

Salivary gland proteins of the human malaria vector, Anopheles dirus B (Diptera: Culicidae)

“…While the female glands are organized in two identical lateral lobes and a medial lobe, the salivary glands of males consist of a single small lobe. The female gland is similar to the salivary glands of Aedes, Culex and Anopheles species 17,23,29,53 . Previous studies reported that the salivary glands of male Aedes and Culex mosquitoes are composed of three identical lobes, all of them formed by cells morphologically similar to that of the female proximal portion of the lateral lobes 43 .…”

“…darlingi) is at least 10% less than that of sugar-fed controls, small differences in the amount of proteins are difficult to visualize in Coomassie Blue stained gels and/or silver stained gels 12 . ORR et al 29 observed a change in the salivary gland cells 24 hours after Ae. aegypti females had taken blood meals; the nucleoli of the median and lateral acini became greatly enlarged and there was a concomitant increase in RNA around the nuclei.…”

“…In addition, the saliva contains immunogens that cause human IgE and lymphocyte-mediated hypersensitivities 30 . Analyses of salivary gland proteins of hematophagous mosquitoes have been reported in Aedes aegypti 17,29,48 , Anopheles stephensi 45,53 , An. gambiae 1,10 , An.…”

Insect–malaria parasites interactions: the salivary gland

“…So far, no chemical attractants for sporozoites have been identified in mosquito salivary glands; however, the accumulation of parasites in the vicinity of the preferred invasion regions of the glands may suggest the participation of a taxic mechanism in the homing (Golenda et al, 1990). This could be mediated by no yet identified soluble molecules released by salivary glands or by a topological distribution of ligand carbohydrate residues (Orr et al, 1961;Perrone et al, 1986) that present an increasing gradient on the vicinity of the organ.…”

Role of Saliva in Blood-Feeding by Arthropods

“…It is involved in dissolution of solid sugar (21) and in lubrication of the feeding stylets in mosquitoes (54). In hard ticks, the salivary apparatus contributes to ion and water metabolism by excreting the excess water acquired from the blood meal (7, 42).…”