Premium
Aquaporin‐1 associated with hepatic arterial capillary proliferation on hepatic sinusoid in human cirrhotic liver
Author(s) -
Yokomori Hiroaki,
Oda Masaya,
Yoshimura Kazunori,
Kaneko Fumihiko,
Hibi Toshifumi
Publication year - 2011
Publication title -
liver international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.873
H-Index - 110
eISSN - 1478-3231
pISSN - 1478-3223
DOI - 10.1111/j.1478-3231.2011.02610.x
Subject(s) - sinusoid , pathology , immunostaining , lobules of liver , biology , aquaporin 1 , hepatic stellate cell , in situ hybridization , biliary tract , immunohistochemistry , medicine , messenger rna , water channel , gene , engineering , inlet , mechanical engineering , biochemistry
Background Aquaporins ( AQP s) are key regulators not only of water transport in the cytoplasm but also of angiogenesis. Although AQP s in the normal hepatobiliary system have been studied in mammals, little is known about the localization and changes of AQP s in the hepatic microvascular system including sinusoids in cirrhotic liver, which might contribute to portal hypertension. Aims We designed this study to examine the localization of AQP 1 in human cirrhotic liver. Methods Surgical wedge biopsy specimens were obtained from non‐cirrhotic portions of human livers (normal control) and from cirrhotic livers ( LC ) ( C hild A ‐ LC and C hild C ‐ LC ). Immunostaining, W estern blotting, in situ hybridization ( ISH ) and laser‐captured microdissection ( LCM ) were conducted. Results In control liver tissue, AQP 1 was localized mainly in the portal venules, hepatic arterioles and bile ducts in the portal tract, although AQP 1 was detected only slightly in the sinusoids. In cirrhotic liver tissue, AQP 1 expression was evident, aberrantly observed on periportal sinusoidal endothelial cells corresponding to the capillarized sinusoids, on the proliferated arterial capillaries opening into the sinusoid in the generating hepatic nodule and on proliferated bile ductules at the peripheral edge of nodules and fibrotic septa. In cirrhotic liver, overexpression of AQP 1 at protein and mRNA levels was demonstrated, respectively, using W estern blot and ISH . AQP ‐1 of mRNA level in sinusoid was confirmed using LCM . Conclusions Aberrant expressions of AQP 1 in periportal sinusoidal regions in human cirrhotic liver indicate the proliferation of arterial capillaries directly connected to the sinusoids, contributing to microvascular resistance in cirrhosis.