A study on PP cells in the chicken pancreas

从鸡胰腺中分离到一种肽，称为禽胰多肽（APP）。采用STERNBERGER的过氧化物酶抗过氧化物酶法，用鸡胰腺特异性抗血清进行了检测。应用免疫组织化学方法对APP细胞进行了研究，发现APP细胞为内分泌细胞，与A、B和D细胞不同。胰多肽（PP）细胞数量众多，分布于外分泌实质中。结果发现，头部区域含有最多的PP细胞，其次是身体，尾部的数量最少。PP细胞的头部和身体区域集中在最接近十二指肠的近端。腹叶背侧部和脾叶中仅少数PP细胞，胰高血糖素α细胞优先出现。PP细胞呈多角形或梭形，外分泌细胞间突起较长，突起与毛细血管相连，A、B胰岛未见PP细胞。D细胞分布于A、B胰岛的外周，并散在分布于外分泌组织中。PP细胞在外分泌薄壁组织中的数量与D细胞大致相同。在任何情况下都没有两个肽免疫反应性定位在相同的细胞。在PP细胞中未检测到甲醛诱导的荧光。PP细胞与5-羟色胺和芳香族层氨酸脱羧酶（AADC）抗体呈免疫组化反应。PP细胞对儿茶酚胺合成酶和某些神经肽的抗血清无免疫反应，AChE阳性神经纤维支配外分泌实质、闰管细胞和血管平滑肌。没有证据表明PP细胞有丰富的AChE阳性神经纤维支配。

A peptide, referred to as avian pancreatic polypeptide(APP), has been isolated from the pancreas of chicken. By STERNBERGER's peroxidaseantiperoxidase method using a specific antiserum against app chicken pancreas cxamined. APP cells were also studied by the immunohistochemistry after fluorescence microscopy by FALCK-HILLARP's method.The immunoreactivity was localized to a population of endocrine cells, distinct from the A, B and D cells. Pancreatic polypeptide(PP) cells were numerous and disseminated in the exocrine parenchyma. It was found that the head region contained the greatest number of PP cells with the body next and the tail having the smallest number. PP cells of the head and body regions were concentrated in the closest to the proximal duodenum. Only a few PP cells were localized in the dorsal part of ventral lobe and in the splenic lobe where the glucagon-containing a cells occurred preferentially. PP cells were polygonal or pyramid-shaped and had elongated processes among the exocrine cells, and processes were associated with capillaries.No PP cells were found in the A and B islets. D cells were distributed peripherally in A and B islets and were dispersed in the exocrine tissue. PP cells were roughly as numerous in the exocrine parenchyma as D cells. In no case did the two peptide-immunoreactivity localized in the same cells. No formaldehyde-induced fluorescence was detected in the PP cells. But PP cells exhibited immunohistochemical reactions with anti-serotonin and aromatic laminoacid decarboxylase(AADC) sera. No PP cells showed immunoreactivity for antisera against catecholamine synthesizing enzymes and some kinds of neuropeptides.AChE-positive nerve fibers innervated the exocrine parenchyma, the intercalated ductular cells and the smooth muscles of blood vessels. There is no evidence to show that PP cells were richly innervated with AChE-positive nerve fibers.