血管活性肠肽(VIP)在文昌鱼体内免疫组织化学定位的研究

本文用免疫组织化学技术首次发现VIP在文昌鱼体内有广泛分布。结果表明,VIP免疫阳性反应出现在消化道各部位,如中肠突、中肠前和后部以及后肠、神经系统、发育早期性腺以及口腔前庭两侧皮下组织中。

IMMUNOHISTOCHEMICAL LOCALIZATION OF VASOACTIVE INTESTINAL POLYPEPTIDE IN AMPHIOXUS

Wide distribution of vasoactive intestinal polypeptide (VIP) in amphioxus was found by immunohistochemical technique. The present study indicated that VIP immuno-positive endocrine cells existed in various regions of the digestive tract, for example, in mid-gut diverticulum, in anterior and posterior of mid-gut and in hind-gut. Many columnar endocrine cells in the front part of the mid-gut diverticulum showed strong immuno-reaction, but posteriormid-gut diverticulum was negative. Immuno-positive cells were found in the anterior region of mid-gut and the cytoplasmic top of these cells extended to the intestinal cavity, while other tissues were negative. A few scallered VIP endocrine cells in the posterior region of mid-gut were only found at the dorsum of the digestive tube. A lot of dense strong immuno-positive VIP endocrine cells were observed in the hind-gut. On the other hand, nerve cells and fibers in the brain vesicle and spinal cord showed immuno-positive reactions in different degrees. There were more than 10 nerve cells and fibers showing positive reaction at the dorsum of brain vesicle, the majority of them were nerve cells of small type, a few were large cells. The ventral region of the brain vesicle was negative. In addition, immunopositive reactions were also found in early spermatogenic cells, oogonia and subcutaneous tissues on both sides of the mouth cavity. These results supplied the morphological evidence for the physiological role of amphioxus and the evolution of polypeptide hormone.