LIVER. 



223 



capillary circulation in the liver, in addition to the sinusoidal, but the 

 former is essentially confined to the connective tissue. 



Microscopic appearance of the adult liver. In sections of the adult 

 human liver there will be seen clumps of connective tissue which contain 

 branches of the portal vein, hepatic artery, and bile ducts, the last being 

 easily distinguished by their columnar or cuboidal epithelium (Fig. 250). 

 Lymphatic vessels and nerves (non-medullated fibers but no nerve cells) 

 may also be found in this connective tissue. There is a tendency for the 

 connective tissue areas to anastomose with one another. Pathologically 



FIG. 251. LIVER OF A PIG. (Radasch.) 



The lobules have artificially shrunken from the interlobular tissue, a; b, bile duct; c, hepatic artery; d, 

 interlobular vein (a branch of the portal); e, trabeculae; f, central vein. 



in man, but normally in certain animals, as in the pig, this anastomosis is 

 complete and polygonal areas of hepatic trabeculae are thus made promi- 

 nent (Fig. 251). These are the lobules of the liver, and the connective 

 tissue around them is the interlobular connective tissue, containing inter- 

 lobular veins (the branches of the portal). In the center of each lobule is 

 a large sinusoid, the central vein (sometimes there are two). Toward it 

 the sinusoids converge from the interlobular veins on all sides (Fig. 252), 

 and from it the hepatic trabeculae radiate. The central veins open, 

 usually at right angles, into the larger sublobular veins (Fig. 253). The 

 latter, being derived from sinusoids, have notably little connective tissue 



