Análise quantitativa de células digestivas e regenerativas do intestino médio de Melipona quadrifasciata anthidioides (Hymenoptera; Apidae)

• Autor(a) principal: Fernandes, Kenner Morais
• Data de Publicação: 2009
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/2342
• topic: Abelha sem ferrão; Ventrículo; Meliponini; Dapi; Stingless bee; Ventricle; Meliponini; Dapi; CNPQ::CIENCIAS BIOLOGICAS::BIOLOGIA GERAL

Bees have economic importance for their role as crops pollinators, production of honey, wax and propolis. The stingless bees (tribe Meliponini) are specific pollinators of many native plant species, most notably the species Melipona quadrifasciata anthidioides (Kerr et al., 1996). Thus, a deeper understanding of the biology of this species may facilitate a better management and conservation of them. Digestion and absorption of virtually all nutrients ingested by the insects take place in the midgut. The epithelium is composed of three cell types: digestive cells, the regenerative cells and endocrine cells. The development time of egg into imago does not differ greatly between varieties, the longevity being very uneven. In workers of several stingless bees species, life after emergence is around 50 days, while in Queens it can reach 7 years. Some authors state that, although it is common the occurrence of mitosis in regenerative cells in adult specimens of various insect groups, this does not occur in Hymenoptera. Therefore, it is expected that longevity of Hymenoptera individuals is directly related to the number of regenerative cells at the time of emergence to adulthood, set of the pupation. In the present study we associate the classic histology with the technique of observing the midgut in full assembly (whole mount preparation), allowing a better analysis of the digestive cells and regenerative potential mitosis as well. Variations were observed along the midgut and between varieties with respect to the digestive cells and nests of regenerative cells. The variations in size and amount of digestive and regenerative cells from the midgut areas of the same individual and among the varieties can indicate possible physiological differences between segments of this organ in the digestive process. The number of regenerative cells varied slightly among the varieties, even if compared with queens of 3 years, showing that there is possibly a renewal in the nests of regenerative cells. However it was observed only one image of mitosis, of all samples analyzed.This way it can be concluded that the mechanism of renewal of gut epithelial cells can do without this process. The mechanisms towards the maintenance and renewal of regenerative cells in the midgut of Hymenoptera remain little known. This study suggests that the regenerative cells of M. quadrifasciata anthidioides may be stem cells, despite the small number of mitosis, and that there is a direct relationship between the number of regenerative cells and the longevity of individuals.