关键词: 意大利蜜蜂, 胸部肌肉, 5-溴-2-脱氧脲嘧啶, 胚后发育, 免疫组织化学

Abstract: 【Aim】 This study aims to understand the postembryonic development of the thoracic muscles of the Italian honey bee, Apis mellifera ligustica, so as to provide some theoretical support for the study of animal muscle development and pathology, and to present a valuable insect model system to investigate muscle regeneration in vivo. 【Methods】 The postembryonic developmental process and structure characteristics of the thoracic muscles of A. m. ligustica were observed and compared by using hematoxylin and eosin (HE) staining and 5-bromo-2-deoxyuridine (BrdU) incorporation. 【Results】 The thoracic muscles of A. m. ligustica larvae are derived from myoblasts formed during embryonic development. Muscle development is accomplished through the fusion of fusion-competent myoblasts (FCMs) and founder cells (FCs), and the division of myoblasts and muscle cells. In the early stages of the development of A. m. ligustica pupa, most of the larval muscles degenerate and disappear. Adult thoracic muscles originate from three myoblast nests of two muscle cell groups, of which dorsal longitudinal muscles (DLMs) mainly originate from one myoblast nest of dorsal fan-shaped cell group, and other muscles originate from two myoblast nests of the ventral spindle cell group. Adult myoblasts of the myoblast nest continuously divide and proliferate. These divided cells expand and extend in specific directions. These cells become muscle fibers after the myofilaments are formed, and then multiple cells form a muscle bundle. These muscle bundles make up the entire muscles of the adult thorax. 【Conclusion】 The developmental modes of muscles of A. m. ligustica are different between its larvae and adults, and also different from those of Drosophila.

Key words: Apis mellifera ligustica, thoracic muscles, BrdU, postembryonic development, immunohistochemsitry