An experimental study into the cause of the increased portal pressure in portal cirrhosis / by Frederick C. Herrick.

  • Herrick, Frederick C.
Date:
[1907]
Catalogue details

Licence: In copyright

Credit: An experimental study into the cause of the increased portal pressure in portal cirrhosis / by Frederick C. Herrick. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    throughout their entire course accompany the larger branches of the portal vein (to which as well as to the adjacent larger bile ducts they supply nutrient capillaries). These branches enter into numerous anastomotic communications among themselves. The small capillaries pass mainly from the periphery of the acinus into the capillaries, however, that lie in the thicker connective tissue upon the larger venous and biliary branches and pass over chiefly into two venous trunks that, accompanying the corresponding arterial branches for some distance, empty into branches of the portal vein. Individual arterial branches pass up to the surface of the liver, where they form a wide nutritive network, particularly under the peritoneal covering. The small venous radicles collecting from this point also reach the ramifications of the portal vein.” The arterial supply thus passes through a capillary system ar- ranged in Glisson’s capsule about the portal interlobular veins and its pressure becomes reduced to an ordinary venous one. This arterial division has also been described as resulting in the forma- tion of three or four arterioles which wind spirally about their accompanying portal vein. This spiral arrangement can be demon- strated in microscopical sections. 2. The vaso-motor influence in balancing these flows must be considered. Thus it has been shown by Bayliss and Starling that a stimulation of the splanchnic nerves causes an increased flow of blood from the liver, although the portal vein was tied. It has also been shown by Mall8 that the portal vein receives fibers from the splanchnics. In my work in making the Eck fistula, I have frequently noticed slow vermicular contractions of the portal vein following mechanical stimulation of its walls. Two Italian authors ascribe both constrictor and dilator fibers to the splanchnic nerves and dilator fibers to the vagus (Cavazzani and Manca9). Thus, in the normal liver through the medium of these two fac- tors the arterial and portal pressures reach a common level at the points where their currents join to form the intralobular veins. If the arterial supply to a given area is relatively increased a disturb- ance of the balance will occur. Also, a fibrosis will make the vessel 8 Mall, Arch. f. Physiol1892, 409 (from Schafer). 9 Cavazzani and Manca, Arch. ital. de biol., 1895, xxiv, 35, 295.