Pannarale Luigi, Onori Paolo, Borghese Federica, Conte Davide, Gaudio Eugenio
Department of Human Anatomy, State University "La Sapienza" of Rome.
Ital J Anat Embryol. 2007 Jan-Mar;112(1):1-12.
The hepatic artery plays an important role in the nourishment of liver parenchyma. The arterial distribution generates debate on where the artery terminates in the liver although is accepted that terminal branching of hepatic artery opened into sinusoids and form arterio-portal anastomosis. This implies that sinusoids are fed by both arterial and portal vessels characterized by different pressures. The presence of a double feeding to the sinusoids from the vena porta, at a pressure of 6-7 cm H2O, and from the hepatic artery, at a pressure of 12-25 cm H2O, has generated many studies for the need to explain the prevalence of flow from the vena porta. For this reason, we have studied the terminal hepatic artery branches in the rat by using special microvascular corrosion casting procedure which makes possible to better follow the hepatic artery terminal branches. Twelve young sexually mature male and female Wistar rats were used in this study. More than one hundred vascular corrosion casts of terminal hepatic arterioles were studied by Scanning Electron Microscopy. Histological samples were prepared using standard techniques for light microscopy. The experimental approach allow to easily follow the three-dimensional course of hepatic artery branches which is extremely difficult in standard injections. In all our observations of the rat liver vascular corrosion casts, terminal hepatic artery branches do not end directly in the sinusoidal beds. Terminal hepatic artery branches end into peribiliary plexus, periportal plexus and single capillaries of the portal space. We have not found any arterio-venous shunt nor any arterial vessel flowing into a venous vessel or a sinusoid. This means that only venous blood at a lowered pressure reaches the vena porta branches and the sinusoids.
肝动脉在肝实质的营养供应中起着重要作用。尽管人们普遍认为肝动脉的终末分支开口于肝血窦并形成动门脉吻合，但动脉分布仍引发了关于肝动脉在肝脏中终止位置的争论。这意味着肝血窦由压力不同的动脉和门静脉供血。门静脉以6 - 7厘米水柱的压力、肝动脉以12 - 25厘米水柱的压力双重供血至肝血窦，这引发了许多关于解释门静脉血流占优势原因的研究。因此，我们采用特殊的微血管铸型技术研究了大鼠肝动脉的终末分支，该技术使更好地追踪肝动脉终末分支成为可能。本研究使用了12只性成熟的年轻Wistar大鼠，雌雄皆有。通过扫描电子显微镜研究了一百多个肝动脉终末小动脉的血管铸型。使用标准技术制备组织学样本用于光学显微镜观察。该实验方法能够轻松追踪肝动脉分支的三维走向，而这在标准注射中极其困难。在我们对大鼠肝脏血管铸型的所有观察中，肝动脉终末分支并非直接终止于肝血窦床。肝动脉终末分支终止于胆小管周围丛、门管周围丛以及门管区的单个毛细血管。我们未发现任何动静脉分流，也未发现任何动脉血管流入静脉血管或肝血窦。这意味着只有低压的静脉血到达门静脉分支和肝血窦。
