Ishay Jacob S, Pertsis Vitaly, Neufeld Arnon, Bergman David J
Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978 Israel.
J Nanobiotechnology. 2004 Jan 11;2(1):1. doi: 10.1186/1477-3155-2-1.
The present study set out to elucidate the structure and function of the large subcuticular air sacs encountered in the gaster of the Oriental hornet Vespa orientalis (Hymenoptera, Vespinae). Gastral segments I, II, III, together with the anterior portion of segment IV, comprise the greater volume of the gaster, and inside them, beneath the cuticle, are contained not only structures that extend throughout their entire length, like the alimentary canal, and the nerve cord with its paired abdominal ganglia, situated near the cuticle in the ventral side, but also the heart, which is actually a muscular and dorsally located blood vessel that pumps blood anteriorly, toward the head of the hornet. The mentioned structures take up only a small volume of the gaster, while the rest is occupied by air sacs and tracheal ducts that also extend longitudinally. Interposed between the two air sacs, there is a hard partition and above it, at the center - a paired tracheal duct that extends the entire length of the air sacs. The endothelium of the air sacs is very anfractuous, thereby enlarging and strengthening the surface area. In each gastral segment there is an aperture for the entry of air, namely, a spiracle. Additionally, in each segment, in the antero-lateral aspect of its tergum and situated between two successive segments, there is an intersegmental conjunctive bearing parallel slits of 1-2 microM in width and 10-30 microM in length. The latter are arranged concentrically around bundles of tracheae that traverse the cuticle from segment to segment. From the upper rims of the slits are suspended downward fringe-like structures or "shutters" ranging between 3-10 microM in length. We discuss the possibility that the Oriental hornet resorts to internal circulation of air, along with a thermoelectric heat pump mechanism, in order to achieve cooling and thermoregulation of its body.
本研究旨在阐明东方胡蜂（膜翅目，胡蜂科）腹部所见大型皮下气囊的结构与功能。腹部的第一、二、三节以及第四节的前部构成了腹部的大部分体积，在这些节段内部，在角质层下方，不仅包含贯穿其全长的结构，如消化道，以及位于腹侧靠近角质层的神经索及其成对的腹神经节，还包含心脏，心脏实际上是一个位于背部的肌肉性血管，将血液向前泵送至胡蜂头部。上述结构仅占据腹部的一小部分体积，其余部分则被同样纵向延伸的气囊和气管导管占据。在两个气囊之间有一个硬隔板，在其上方中央有一对气管导管，其长度与气囊相同。气囊的内皮非常曲折，从而扩大并增强了表面积。在每个腹部节段都有一个空气进入的孔口，即气门。此外，在每个节段中，在背板的前外侧，位于两个连续节段之间，有一个节间连接组织，带有宽度为1 - 2微米、长度为10 - 30微米的平行狭缝。后者围绕着从一个节段穿过角质层到另一个节段的气管束同心排列。从狭缝的上边缘向下悬挂着长度在3 - 10微米之间的流苏状结构或“百叶窗”。我们讨论了东方胡蜂借助空气内部循环以及热电热泵机制来实现身体冷却和体温调节的可能性。
