The salivary glands of Hyalomma anatolicum anatolicum: Nature of salivary gland components and their role in tick attachment and feeding

Abstract

Gill H. S. and Walker A. R. 1988. The salivary glands of Hyalomma anatolicum anatolicum: nature of salivary gland components and their role in tick attachment and feeding. International Journal for Parasitology 18: 83–93. A study was made of the histochemistry of the salivary glands and tick feeding sites of H. a. anatolicum during feeding. The attachment cement of H. a. anatolicum was lipoprotein in nature and appeared to have been derived from a cells of type II, and d and e cells of type III acini in the salivary glands. The secretory granules of these cells had similar histochemical properties to the cement. Deposits of glycoprotein materials were located at tick feeding sites in dermal tissues adjacent to the mouthparts and not in the attachment cement. This polysaccharide material is presumed to be secreted by b and c cells of type II acini. Strong aminopeptidase and moderate acid phosphatase activity was found localized in the cement cone and not in the tissues. Deposits of non-specific esterase material, probably derived from b, c 1 and c 3 cells of type II acini in the glands were demonstrated at tick feeding sites adjacent to the mouthparts. It is presumed that the esterase might increase vascular permeability in the dermis of the hosts by its direct action on mast-cells. A steady increase in ATPase and alkaline phosphatase activity in the interstitial cells and the lumenal border of type II and III acini during feeding suggests a possible role in osmoregulation. Despite the strong reactions for several oxidoreductases and other phosphatases in the salivary glands of H. a. anatolicum, no activity for these enzymes was detected in the cement or at feeding sites. The possible role of these salivary components in feeding is discussed.