Histoquímica e ultraestrutura das glândulas salivares das abelhas (Hymenoptera, Apoidea)

Abstract

This is a study of the four types of salivary glands normally occurring in bees. Current histochemical techniques were used to study variation of protein, polysaccharides, nucleic acids and lipids, during the secretory cycle. Ultrastructural techniques were used to follow the cellular organelles through the elaboration and elimination of secretory products. Much quantitative variation was found in all substances studied, between glands and between stages of the same gland. The thoracic salivary gland of Melipona was found to secrete protein, and the head gland lipids. Glycogen was found only in the glands of very young bees, and is thought to be an embryonic remnant. Electron microscopy showed that the cellular organelles evolve during the secretory cycle according to what is generally known for cells with similar functions. The Golgi apparatus was not seen in Xylocopa and Colletes, probably because part of the secretion products are stored in vacuoles. The data permit to derive thoracic salivary gland types 1, 2 and 3 from type 4. Type 1 would result from the disappearance of the central (zymogenic) cells; type 2 by reduction only of the number of these cells; type 3 by disappearance of the peripheral (parietal) cells.