Terada T, Nakanuma Y
Second Department of Pathology, Kanazawa University School of Medicine, Japan.
Gastroenterology. 1995 Apr;108(4):1236-45. doi: 10.1016/0016-5085(95)90225-2.
BACKGROUND/AIMS: Although pancreatic enzymes have been found in hilar intrahepatic bile ducts in adult humans, their expression during human liver development is unclear. The aim of this study was to clarify the temporal expression of pancreatic enzymes at various stages of human liver development.
We immunohistochemically investigated pancreatic alpha-amylase, trypsinogen, and lipase expression in fetal, neonatal, juvenile, and adult human livers.
In hilar duct development, alpha-amylase but not trypsinogen or lipase was expressed in the ductal plate. These three enzymes were expressed in biliary cells migrating into the mesenchyma, in immature ducts in fetal livers, and in maturing and mature ducts in postnatal livers. Their expression was weak and diffusely cytoplasmic in fetal livers, whereas in postnatal livers their expression was strong, granular, and located in the supranuclear cytoplasm. Expression was not found in developing peripheral ducts. These enzymes were expressed in immature hepatocytes (9-25 weeks' gestation) but disappeared thereafter. Enzyme expression was mild in fetal pancreata and strong in adult pancreata.
Pancreatic enzymes may be present in primitive hilar bile ducts and hepatocytes in fetal livers; hilar ducts, hepatocytes, and pancreas may have similar fetal enzymatic profiles. Intrahepatic hilar bile ducts, hepatocytes, and exocrine pancreas may have a common cell lineage.
背景/目的：尽管在成年人体内的肝门部肝内胆管中发现了胰腺酶，但其在人类肝脏发育过程中的表达尚不清楚。本研究的目的是阐明胰腺酶在人类肝脏发育各阶段的时间表达情况。
我们采用免疫组织化学方法研究了胎儿、新生儿、青少年和成人肝脏中胰腺α淀粉酶、胰蛋白酶原和脂肪酶的表达。
在肝门部胆管发育过程中，α淀粉酶在胆管板中表达，而胰蛋白酶原和脂肪酶未表达。这三种酶在迁移到间充质的胆管细胞、胎儿肝脏的未成熟胆管以及出生后肝脏的成熟和成熟胆管中均有表达。它们在胎儿肝脏中的表达较弱且呈弥漫性胞质表达，而在出生后肝脏中表达较强、呈颗粒状且位于核上胞质中。在发育中的外周胆管中未发现表达。这些酶在未成熟肝细胞（妊娠9 - 25周）中表达，但此后消失。酶在胎儿胰腺中的表达较弱，在成人胰腺中表达较强。
胰腺酶可能存在于胎儿肝脏的原始肝门部胆管和肝细胞中；肝门部胆管、肝细胞和胰腺可能具有相似的胎儿酶谱。肝内肝门部胆管、肝细胞和外分泌胰腺可能有共同的细胞谱系。
